Added some empty help info docs for JSORestrictionsChecker and LongFromJSNIChecker.  Added infrastructure for propagating the extra help into to the logger.

Review by: knorton


git-svn-id: https://google-web-toolkit.googlecode.com/svn/trunk@2344 8db76d5a-ed1c-0410-87a9-c151d255dfc7