Merge branch 'release/1.7-RC5' into develop
Bump version number to RC5+ post RC5 release
check file size at client before upload.
Refactor how ticket count on open queue is done depending on 'show assigned tickets' settings.
 -> Open - only contains unasssined tickets if 'show assigned tickets' is off.
Show assigned to column based on flag - which now factors in if assigned tickets are being shown on open queue.
Add Answered queue to advanced search
Add ability to filter by unassigned on advanced search.
Add help topics to advanced search and csv export
Fix method name typo
Make lint happy
Gracefully return when file info or max size are not set.
Remove default max limit - no size limit is assumed.
Remove file type & size limit on staff control panel (current limits are meant for clients only).
Move $_FILES reformatting & validation to class.file.php
Change how validation is done to allow for downstream validation & fixups.
Add ticket thread class.
Fully implement thread entry class and types (Note, Message & Response)
Add method to sanitize rich/html text. Addd html encode/decode methods. Remove html encode on display (encoded text saved in db)
Refactor ticket related methods/utils to use thread model.
Balance html tags & neutralize unsafe tags on emailed html'ed emails.
Decode html entities - outgoing emails are plain text for now
Don't show reply/response section on new ticket form if the staff can NOT post replies... also checked in Ticket::open().