Misc. Forum + Chat Bugfixes

Widened forum titles and chat text DB fields to permit full-width
Unicode. Adjusted CSS to make markup look right in edge cases. Better
handled error messages on Forum page.
Clarified field lengths and broke out showError
Typo in comment
Merge pull request #973 from AdmiralJota/960_961_959_forum_fixes

Misc. Forum + Chat Bugfixes