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/scss/main.scss

@@ -86,6 +86,7 @@ $layer-dialog: 1000;
 // Child Stylesheets ///////////////////////////////////////////////////////////////////////////////////////////////////
 
 @import 'classes';
+@import 'markdown';
 @import 'tags';
 @import 'views';
 

src/scss/markdown.scss

@@ -0,0 +1,22 @@
+/*
+Crafting Guide - markdown.scss
+
+Copyright (C) 2015 by Redwood Labs
+All rights reserved.
+*/
+
+.markdown {
+
+    p {
+        font-family: $font-family-normal;
+        font-size: $font-size-normal;
+        line-height: $font-size-normal + 0.25em;
+    }
+
+    img {
+        position: relative; left: 50%;
+        @include transform(translateX(-50%));
+        margin: 2em 0;
+        text-align: center;
+    }
+}

src/scss/templates/item_page.scss

@@ -31,15 +31,6 @@ All rights reserved.
             }
         }
 
-        .description {
-            margin-bottom: 4em;
-
-            p {
-                font-family: $font-family-normal;
-                font-size: $font-size-large;
-            }
-        }
-
         .recipes {
             display: none;