diff --git a/lib/Parsedown/ParsedownExtra.php b/lib/Parsedown/ParsedownExtra.php
new file mode 100644
index 0000000..1592ad2
--- /dev/null
+++ b/lib/Parsedown/ParsedownExtra.php
@@ -0,0 +1,686 @@
+<?php
+
+#
+#
+# Parsedown Extra
+# https://github.com/erusev/parsedown-extra
+#
+# (c) Emanuil Rusev
+# http://erusev.com
+#
+# For the full license information, view the LICENSE file that was distributed
+# with this source code.
+#
+#
+
+class ParsedownExtra extends Parsedown
+{
+	# ~
+	
+	const version = '0.8.0';
+	
+	# ~
+	
+	function __construct()
+	{
+		if (version_compare(parent::version, '1.7.1') < 0)
+		{
+			throw new Exception('ParsedownExtra requires a later version of Parsedown');
+		}
+		
+		$this->BlockTypes[':'] []= 'DefinitionList';
+		$this->BlockTypes['*'] []= 'Abbreviation';
+		
+		# identify footnote definitions before reference definitions
+		array_unshift($this->BlockTypes['['], 'Footnote');
+		
+		# identify footnote markers before before links
+		array_unshift($this->InlineTypes['['], 'FootnoteMarker');
+	}
+	
+	#
+	# ~
+	
+	function text($text)
+	{
+		$Elements = $this->textElements($text);
+		
+		# convert to markup
+		$markup = $this->elements($Elements);
+		
+		# trim line breaks
+		$markup = trim($markup, "\n");
+		
+		# merge consecutive dl elements
+		
+		$markup = preg_replace('/<\/dl>\s+<dl>\s+/', '', $markup);
+		
+		# add footnotes
+		
+		if (isset($this->DefinitionData['Footnote']))
+		{
+			$Element = $this->buildFootnoteElement();
+			
+			$markup .= "\n" . $this->element($Element);
+		}
+		
+		return $markup;
+	}
+	
+	#
+	# Blocks
+	#
+	
+	#
+	# Abbreviation
+	
+	protected function blockAbbreviation($Line)
+	{
+		if (preg_match('/^\*\[(.+?)\]:[ ]*(.+?)[ ]*$/', $Line['text'], $matches))
+		{
+			$this->DefinitionData['Abbreviation'][$matches[1]] = $matches[2];
+			
+			$Block = array(
+				'hidden' => true,
+			);
+			
+			return $Block;
+		}
+	}
+	
+	#
+	# Footnote
+	
+	protected function blockFootnote($Line)
+	{
+		if (preg_match('/^\[\^(.+?)\]:[ ]?(.*)$/', $Line['text'], $matches))
+		{
+			$Block = array(
+				'label' => $matches[1],
+				'text' => $matches[2],
+				'hidden' => true,
+			);
+			
+			return $Block;
+		}
+	}
+	
+	protected function blockFootnoteContinue($Line, $Block)
+	{
+		if ($Line['text'][0] === '[' and preg_match('/^\[\^(.+?)\]:/', $Line['text']))
+		{
+			return;
+		}
+		
+		if (isset($Block['interrupted']))
+		{
+			if ($Line['indent'] >= 4)
+			{
+				$Block['text'] .= "\n\n" . $Line['text'];
+				
+				return $Block;
+			}
+		}
+		else
+		{
+			$Block['text'] .= "\n" . $Line['text'];
+			
+			return $Block;
+		}
+	}
+	
+	protected function blockFootnoteComplete($Block)
+	{
+		$this->DefinitionData['Footnote'][$Block['label']] = array(
+			'text' => $Block['text'],
+			'count' => null,
+			'number' => null,
+		);
+		
+		return $Block;
+	}
+	
+	#
+	# Definition List
+	
+	protected function blockDefinitionList($Line, $Block)
+	{
+		if ( ! isset($Block) or $Block['type'] !== 'Paragraph')
+		{
+			return;
+		}
+		
+		$Element = array(
+			'name' => 'dl',
+			'elements' => array(),
+		);
+		
+		$terms = explode("\n", $Block['element']['handler']['argument']);
+		
+		foreach ($terms as $term)
+		{
+			$Element['elements'] []= array(
+				'name' => 'dt',
+				'handler' => array(
+					'function' => 'lineElements',
+					'argument' => $term,
+					'destination' => 'elements'
+				),
+			);
+		}
+		
+		$Block['element'] = $Element;
+		
+		$Block = $this->addDdElement($Line, $Block);
+		
+		return $Block;
+	}
+	
+	protected function blockDefinitionListContinue($Line, array $Block)
+	{
+		if ($Line['text'][0] === ':')
+		{
+			$Block = $this->addDdElement($Line, $Block);
+			
+			return $Block;
+		}
+		else
+		{
+			if (isset($Block['interrupted']) and $Line['indent'] === 0)
+			{
+				return;
+			}
+			
+			if (isset($Block['interrupted']))
+			{
+				$Block['dd']['handler']['function'] = 'textElements';
+				$Block['dd']['handler']['argument'] .= "\n\n";
+				
+				$Block['dd']['handler']['destination'] = 'elements';
+				
+				unset($Block['interrupted']);
+			}
+			
+			$text = substr($Line['body'], min($Line['indent'], 4));
+			
+			$Block['dd']['handler']['argument'] .= "\n" . $text;
+			
+			return $Block;
+		}
+	}
+	
+	#
+	# Header
+	
+	protected function blockHeader($Line)
+	{
+		$Block = parent::blockHeader($Line);
+		
+		if ($Block !== null && preg_match('/[ #]*{('.$this->regexAttribute.'+)}[ ]*$/', $Block['element']['handler']['argument'], $matches, PREG_OFFSET_CAPTURE))
+		{
+			$attributeString = $matches[1][0];
+			
+			$Block['element']['attributes'] = $this->parseAttributeData($attributeString);
+			
+			$Block['element']['handler']['argument'] = substr($Block['element']['handler']['argument'], 0, $matches[0][1]);
+		}
+		
+		return $Block;
+	}
+	
+	#
+	# Markup
+	
+	protected function blockMarkup($Line)
+	{
+		if ($this->markupEscaped or $this->safeMode)
+		{
+			return;
+		}
+		
+		if (preg_match('/^<(\w[\w-]*)(?:[ ]*'.$this->regexHtmlAttribute.')*[ ]*(\/)?>/', $Line['text'], $matches))
+		{
+			$element = strtolower($matches[1]);
+			
+			if (in_array($element, $this->textLevelElements))
+			{
+				return;
+			}
+			
+			$Block = array(
+				'name' => $matches[1],
+				'depth' => 0,
+				'element' => array(
+					'rawHtml' => $Line['text'],
+					'autobreak' => true,
+				),
+			);
+			
+			$length = strlen($matches[0]);
+			$remainder = substr($Line['text'], $length);
+			
+			if (trim($remainder) === '')
+			{
+				if (isset($matches[2]) or in_array($matches[1], $this->voidElements))
+				{
+					$Block['closed'] = true;
+					$Block['void'] = true;
+				}
+			}
+			else
+			{
+				if (isset($matches[2]) or in_array($matches[1], $this->voidElements))
+				{
+					return;
+				}
+				if (preg_match('/<\/'.$matches[1].'>[ ]*$/i', $remainder))
+				{
+					$Block['closed'] = true;
+				}
+			}
+			
+			return $Block;
+		}
+	}
+	
+	protected function blockMarkupContinue($Line, array $Block)
+	{
+		if (isset($Block['closed']))
+		{
+			return;
+		}
+		
+		if (preg_match('/^<'.$Block['name'].'(?:[ ]*'.$this->regexHtmlAttribute.')*[ ]*>/i', $Line['text'])) # open
+		{
+			$Block['depth'] ++;
+		}
+		
+		if (preg_match('/(.*?)<\/'.$Block['name'].'>[ ]*$/i', $Line['text'], $matches)) # close
+		{
+			if ($Block['depth'] > 0)
+			{
+				$Block['depth'] --;
+			}
+			else
+			{
+				$Block['closed'] = true;
+			}
+		}
+		
+		if (isset($Block['interrupted']))
+		{
+			$Block['element']['rawHtml'] .= "\n";
+			unset($Block['interrupted']);
+		}
+		
+		$Block['element']['rawHtml'] .= "\n".$Line['body'];
+		
+		return $Block;
+	}
+	
+	protected function blockMarkupComplete($Block)
+	{
+		if ( ! isset($Block['void']))
+		{
+			$Block['element']['rawHtml'] = $this->processTag($Block['element']['rawHtml']);
+		}
+		
+		return $Block;
+	}
+	
+	#
+	# Setext
+	
+	protected function blockSetextHeader($Line, array $Block = null)
+	{
+		$Block = parent::blockSetextHeader($Line, $Block);
+		
+		if ($Block !== null && preg_match('/[ ]*{('.$this->regexAttribute.'+)}[ ]*$/', $Block['element']['handler']['argument'], $matches, PREG_OFFSET_CAPTURE))
+		{
+			$attributeString = $matches[1][0];
+			
+			$Block['element']['attributes'] = $this->parseAttributeData($attributeString);
+			
+			$Block['element']['handler']['argument'] = substr($Block['element']['handler']['argument'], 0, $matches[0][1]);
+		}
+		
+		return $Block;
+	}
+	
+	#
+	# Inline Elements
+	#
+	
+	#
+	# Footnote Marker
+	
+	protected function inlineFootnoteMarker($Excerpt)
+	{
+		if (preg_match('/^\[\^(.+?)\]/', $Excerpt['text'], $matches))
+		{
+			$name = $matches[1];
+			
+			if ( ! isset($this->DefinitionData['Footnote'][$name]))
+			{
+				return;
+			}
+			
+			$this->DefinitionData['Footnote'][$name]['count'] ++;
+			
+			if ( ! isset($this->DefinitionData['Footnote'][$name]['number']))
+			{
+				$this->DefinitionData['Footnote'][$name]['number'] = ++ $this->footnoteCount; # » &
+			}
+			
+			$Element = array(
+				'name' => 'sup',
+				'attributes' => array('id' => 'fnref'.$this->DefinitionData['Footnote'][$name]['count'].':'.$name),
+				'element' => array(
+					'name' => 'a',
+					'attributes' => array('href' => '#fn:'.$name, 'class' => 'footnote-ref'),
+					'text' => $this->DefinitionData['Footnote'][$name]['number'],
+				),
+			);
+			
+			return array(
+				'extent' => strlen($matches[0]),
+				'element' => $Element,
+			);
+		}
+	}
+	
+	private $footnoteCount = 0;
+	
+	#
+	# Link
+	
+	protected function inlineLink($Excerpt)
+	{
+		$Link = parent::inlineLink($Excerpt);
+		
+		$remainder = $Link !== null ? substr($Excerpt['text'], $Link['extent']) : '';
+		
+		if (preg_match('/^[ ]*{('.$this->regexAttribute.'+)}/', $remainder, $matches))
+		{
+			$Link['element']['attributes'] += $this->parseAttributeData($matches[1]);
+			
+			$Link['extent'] += strlen($matches[0]);
+		}
+		
+		return $Link;
+	}
+	
+	#
+	# ~
+	#
+	
+	private $currentAbreviation;
+	private $currentMeaning;
+	
+	protected function insertAbreviation(array $Element)
+	{
+		if (isset($Element['text']))
+		{
+			$Element['elements'] = self::pregReplaceElements(
+				'/\b'.preg_quote($this->currentAbreviation, '/').'\b/',
+				array(
+					array(
+						'name' => 'abbr',
+						'attributes' => array(
+							'title' => $this->currentMeaning,
+						),
+						'text' => $this->currentAbreviation,
+					)
+				),
+				$Element['text']
+			);
+			
+			unset($Element['text']);
+		}
+		
+		return $Element;
+	}
+	
+	protected function inlineText($text)
+	{
+		$Inline = parent::inlineText($text);
+		
+		if (isset($this->DefinitionData['Abbreviation']))
+		{
+			foreach ($this->DefinitionData['Abbreviation'] as $abbreviation => $meaning)
+			{
+				$this->currentAbreviation = $abbreviation;
+				$this->currentMeaning = $meaning;
+				
+				$Inline['element'] = $this->elementApplyRecursiveDepthFirst(
+					array($this, 'insertAbreviation'),
+					$Inline['element']
+				);
+			}
+		}
+		
+		return $Inline;
+	}
+	
+	#
+	# Util Methods
+	#
+	
+	protected function addDdElement(array $Line, array $Block)
+	{
+		$text = substr($Line['text'], 1);
+		$text = trim($text);
+		
+		unset($Block['dd']);
+		
+		$Block['dd'] = array(
+			'name' => 'dd',
+			'handler' => array(
+				'function' => 'lineElements',
+				'argument' => $text,
+				'destination' => 'elements'
+			),
+		);
+		
+		if (isset($Block['interrupted']))
+		{
+			$Block['dd']['handler']['function'] = 'textElements';
+			
+			unset($Block['interrupted']);
+		}
+		
+		$Block['element']['elements'] []= & $Block['dd'];
+		
+		return $Block;
+	}
+	
+	protected function buildFootnoteElement()
+	{
+		$Element = array(
+			'name' => 'div',
+			'attributes' => array('class' => 'footnotes'),
+			'elements' => array(
+				array('name' => 'hr'),
+				array(
+					'name' => 'ol',
+					'elements' => array(),
+				),
+			),
+		);
+		
+		uasort($this->DefinitionData['Footnote'], 'self::sortFootnotes');
+		
+		foreach ($this->DefinitionData['Footnote'] as $definitionId => $DefinitionData)
+		{
+			if ( ! isset($DefinitionData['number']))
+			{
+				continue;
+			}
+			
+			$text = $DefinitionData['text'];
+			
+			$textElements = parent::textElements($text);
+			
+			$numbers = range(1, $DefinitionData['count']);
+			
+			$backLinkElements = array();
+			
+			foreach ($numbers as $number)
+			{
+				$backLinkElements[] = array('text' => ' ');
+				$backLinkElements[] = array(
+					'name' => 'a',
+					'attributes' => array(
+						'href' => "#fnref$number:$definitionId",
+						'rev' => 'footnote',
+						'class' => 'footnote-backref',
+					),
+					'rawHtml' => '&#8617;',
+					'allowRawHtmlInSafeMode' => true,
+					'autobreak' => false,
+				);
+			}
+			
+			unset($backLinkElements[0]);
+			
+			$n = count($textElements) -1;
+			
+			if ($textElements[$n]['name'] === 'p')
+			{
+				$backLinkElements = array_merge(
+					array(
+						array(
+							'rawHtml' => '&#160;',
+							'allowRawHtmlInSafeMode' => true,
+						),
+					),
+					$backLinkElements
+				);
+				
+				unset($textElements[$n]['name']);
+				
+				$textElements[$n] = array(
+					'name' => 'p',
+					'elements' => array_merge(
+						array($textElements[$n]),
+						$backLinkElements
+					),
+				);
+			}
+			else
+			{
+				$textElements[] = array(
+					'name' => 'p',
+					'elements' => $backLinkElements
+				);
+			}
+			
+			$Element['elements'][1]['elements'] []= array(
+				'name' => 'li',
+				'attributes' => array('id' => 'fn:'.$definitionId),
+				'elements' => array_merge(
+					$textElements
+				),
+			);
+		}
+		
+		return $Element;
+	}
+	
+	# ~
+	
+	protected function parseAttributeData($attributeString)
+	{
+		$Data = array();
+		
+		$attributes = preg_split('/[ ]+/', $attributeString, - 1, PREG_SPLIT_NO_EMPTY);
+		
+		foreach ($attributes as $attribute)
+		{
+			if ($attribute[0] === '#')
+			{
+				$Data['id'] = substr($attribute, 1);
+			}
+			else # "."
+			{
+				$classes []= substr($attribute, 1);
+			}
+		}
+		
+		if (isset($classes))
+		{
+			$Data['class'] = implode(' ', $classes);
+		}
+		
+		return $Data;
+	}
+	
+	# ~
+	
+	protected function processTag($elementMarkup) # recursive
+	{
+		# http://stackoverflow.com/q/1148928/200145
+		libxml_use_internal_errors(true);
+		
+		$DOMDocument = new DOMDocument;
+		
+		# http://stackoverflow.com/q/11309194/200145
+		$elementMarkup = mb_convert_encoding($elementMarkup, 'HTML-ENTITIES', 'UTF-8');
+		
+		# http://stackoverflow.com/q/4879946/200145
+		$DOMDocument->loadHTML($elementMarkup);
+		$DOMDocument->removeChild($DOMDocument->doctype);
+		$DOMDocument->replaceChild($DOMDocument->firstChild->firstChild->firstChild, $DOMDocument->firstChild);
+		
+		$elementText = '';
+		
+		if ($DOMDocument->documentElement->getAttribute('markdown') === '1')
+		{
+			foreach ($DOMDocument->documentElement->childNodes as $Node)
+			{
+				$elementText .= $DOMDocument->saveHTML($Node);
+			}
+			
+			$DOMDocument->documentElement->removeAttribute('markdown');
+			
+			$elementText = "\n".$this->text($elementText)."\n";
+		}
+		else
+		{
+			foreach ($DOMDocument->documentElement->childNodes as $Node)
+			{
+				$nodeMarkup = $DOMDocument->saveHTML($Node);
+				
+				if ($Node instanceof DOMElement and ! in_array($Node->nodeName, $this->textLevelElements))
+				{
+					$elementText .= $this->processTag($nodeMarkup);
+				}
+				else
+				{
+					$elementText .= $nodeMarkup;
+				}
+			}
+		}
+		
+		# because we don't want for markup to get encoded
+		$DOMDocument->documentElement->nodeValue = 'placeholder\x1A';
+		
+		$markup = $DOMDocument->saveHTML($DOMDocument->documentElement);
+		$markup = str_replace('placeholder\x1A', $elementText, $markup);
+		
+		return $markup;
+	}
+	
+	# ~
+	
+	protected function sortFootnotes($A, $B) # callback
+	{
+		return $A['number'] - $B['number'];
+	}
+	
+	#
+	# Fields
+	#
+	
+	protected $regexAttribute = '(?:[#.][-\w]+[ ]*)';
+}
\ No newline at end of file