Fixes #902 Smilies Improvements

Fixes #902 Smilies Improvements

This doesn't seem to work for subsequent smilies (aliases) any help on that would be appreciated as it worked before I updated my local copy. The smilies cache contains all the aliases as if they were normal smilies so I don't know what's going on...

This also fixes a security vulnerability where the smilie find field could inject arbitrary php into the parser.