Fixed some of the xss vulnerabilities.
Merge branch 'develop' of http://github.com/openwebwork/webwork2 into morexss
Added html escaping to warnings (note if you want to output html from pg you should use $PG->warning_message()
Added scrubbing to messages (only removes scripts right now)
Couldnt resist cleaning up the css for messages a bit.
Merge branch 'develop' of http://github.com/openwebwork/webwork2 into morexss
Initial fix for additional xss vulnerabilities
Fixed unintended change
Merge pull request #167 from goehle/morexss

Additional XSS fixing