Link to markdown syntax documentation

Author: paultcochrane

lib/Language/modules.pod

@@ -48,7 +48,7 @@ To share your module then, do the following:
                 `-- Gargravarr.pm
     =end item
 
-    =item The C<README.md> file is a markdown-formatted text file, which
+    =item The C<README.md> file is a L<markdown-formatted|https://help.github.com/articles/markdown-basics/> text file, which
     will later be automatically rendered as HTML by GitHub.
 
     =item Regarding the C<LICENSE> file, if you have no other preference,