Changed Ruby suffix to ".rb"

Author: dave3d

comment_spell_check/comment_spell_check.py

@@ -54,7 +54,7 @@
     ".c": "text/x-c++",
     ".hxx": "text/x-c++",
     ".py": "text/x-python",
-    ".ruby": "text/x-ruby",
+    ".rb": "text/x-ruby",
     ".java": "text/x-java-source",
     ".txt": "text/plain",
     ".rst": "text/plain",