Log Message:
Update ruby-rdoc to 3.12.2.

=== 3.12.2 / 2013-02-24

* Bug fixes
  * Fixed bug in syntax-highlighting that would corrupt regular expressions.
    Ruby Bug #6488 by Benny Lyne Amorsen.
  * Fixed lexing of character syntax (<code>?x</code>).  Reported by \ 
Xavier
    Noria.
  * Fixed tokenization of % when it is not followed by a $-string type
  * Fixed display of __END__ in documentation examples in HTML output
  * Fixed tokenization of reserved words used as new-style hash keys
  * Fixed HEREDOC output for the limited case of a heredoc followed by a line
    end.  When a HEREDOC is not followed by a line end RDoc is not currently
    smart enough to restore the source correctly.  Bug #162 by Zachary Scott.