Render RMarkdown (.rmd) as Markdown

Author: pchaigno

lib/github/markup/markdown.rb

@@ -25,7 +25,7 @@ class Markdown < Implementation
       }
 
       def initialize
-        super(/md|mkdn?|mdwn|mdown|markdown|litcoffee/)
+        super(/md|rmd|mkdn?|mdwn|mdown|markdown|litcoffee/)
       end
 
       def load

test/markup_test.rb

@@ -35,6 +35,7 @@ class MarkupTest < Test::Unit::TestCase
   def test_knows_what_it_can_and_cannot_render
     assert_equal false, GitHub::Markup.can_render?('README.html')
     assert_equal true, GitHub::Markup.can_render?('README.markdown')
+    assert_equal true, GitHub::Markup.can_render?('README.rmd')
     assert_equal false, GitHub::Markup.can_render?('README.cmd')
     assert_equal true, GitHub::Markup.can_render?('README.litcoffee')
   end

test/markups/README.rmd

@@ -0,0 +1,3 @@
+# Title
+* One
+* Two

test/markups/README.rmd.html

@@ -0,0 +1,6 @@
+<h1>Title</h1>
+
+<ul>
+<li>One</li>
+<li>Two</li>
+</ul>