Ruby: fix nested type name

ex.
  class Module1::A

before:
  Module1 : class

after:
  Module1::A : class

autoload/unite/sources/outline/defaults/ruby.vim

@@ -100,7 +100,7 @@ function! s:outline_info.create_heading(which, heading_line, matched_line, conte
         " Eigen-class
       else
         " Module, Class
-        let word = matchstr(word, '^\s*\%(module\|class\)\s\+\zs\h\w*') . ' : ' . keyword
+        let word = matchstr(word, '^\s*\%(module\|class\)\s\+\zs\h\%(\w\|:\)*') . ' : ' . keyword
       endif
     elseif keyword == 'protected' || keyword == 'private'
       " Accessibility