Show markdown description text on item detail page

* Update build process to *not* copy over prerendered pages during a
  regular build (only during a `dist` build)
* Add dependency on npm "markdown" package and include it in the
  scripts loaded in the default layout
* Update the Item model to be able to load from a *.cg file
* Add an ItemParser to process the `item.cg` file
* Update the general parser to be able to work with HereDoc-style
  text blocks
* Add a markdown-specific stylesheet
* Add a sample of the `item.cg` file format (Advanced Crafting Table)

src/coffee/models/parser_versions/item_parser_v1.coffee

@@ -22,16 +22,17 @@ module.exports = class ItemParserV1 extends CommandParserVersionBase
     # Command Methods ##############################################################################
 
     _command_description: (textParts...)->
-        @_rawData.text ?= ''
-        @_rawData.text += textParts.join ', '
+        @_rawData.description ?= ''
+        @_rawData.description += textParts.join ', '
 
     _command_officialUrl: (officialUrl)->
         if @_rawData.officialUrl? then throw new Error 'duplicate declaration of "officialUrl"'
         if officialUrl.length is 0 then throw new Error 'officialUrl cannot be empty'
         @_rawData.officialUrl = officialUrl
 
-    _command_video: (youTubeId, name)->
+    _command_video: (youTubeId, nameParts...)->
         if not youTubeId?.length then throw new Error 'video declaration requires a YouTubeID'
+        name = nameParts.join ', '
         if not name?.length then throw new Error 'video declaration requires a name'
 
         @_rawData.videos ?= []
@@ -40,6 +41,6 @@ module.exports = class ItemParserV1 extends CommandParserVersionBase
     # Object Building Methods ######################################################################
 
     _buildItem: (rawData, model)->
-        item.description = rawData.description if rawData.description
-        item.officialUrl = rawData.officialUrl if rawData.officialUrl
-        item.videos      = rawData.videos      if rawData.videos
+        model.description = rawData.description if rawData.description
+        model.officialUrl = rawData.officialUrl if rawData.officialUrl
+        model.videos      = rawData.videos      if rawData.videos