* lib/shellwords.rb: Fix rdoc markups.

	* lib/shellwords.rb (Shellwords#shellsplit): Fix a bug where
	  consecutive backslashes in double quotes are all removed except
	  the one at the tail.


git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/branches/ruby_1_9_3@34571 b2dd03c8-39d4-4d8f-98ff-823fe69b080e