Merge pull request #74 from gopher-snakes-2013/bdawg-dan-bugfixes

brandon and dan: reposition and style error messages for sources and topics
brandon/dan: fixed error message and wrapper in PDF viewer
bran/dan: fix logo positioning on hover
bran/dan: Fixed delete snippets/unaffiliated snippets bug
bran/dan: user can delete a source (ajaxified!)
bran/dan:
- user is asked to confirm deletion of source
- unified delete animation for sources, topics, and snippets