CC-4910: Need to properly handle non-200 http status codes in api client

-wrap all service calls in exception
CC-4897: XSS exploit on library page
Merge branch '2.3.x' of dev.sourcefabric.org:airtime into 2.3.x
CC-4897: XSS exploit on library page

-fixed where this was happening on Calendar - show content
CC-4897: XSS exploit on library page
CC-4910: Need to properly handle non-200 http status codes in api client

-fixed
Merge branch '2.3.x' of dev.sourcefabric.org:airtime into 2.3.x
CC-4913: System -> Media Folder: Exception happens when media folder's path contains '<'
CC-4913: System -> Media Folder: Exception happens when media folder's path contains '<'
XSS exploit prevention

- Calendar - Show Contents
- Playlist tooltip in Library page
- Adding track to a show
- Widgets
- Playlist/Webstream title and description
- Smart block expansion
Merge branch '2.3.x' of dev.sourcefabric.org:airtime into 2.3.x
New French po file
Modified schema.xml - made cue_in and cue_out required columns in cc_scheuled and removed default values
XSS exploit prevention

- Calendar -> show content
XSS exploit prevention - audio preview
CC-4921: Now Playing: Cannot insert items into current playing show

-filler time in cc_schedule was not setting cue_in and cue_out
-since we made those colunns not null and removed a default value, we always have to set a value
CC-4919: Library -> Search: Exception happens when switching back to simple search with some illegal input in Advanced Search

-fixed
CC-4865: Password reset -> Cancel -> url is missing base directory

-removed extra '/'
CC-4925: Changing User permissions to a higher level ends up with show editing problems

- added check to ensure user is not an admin before assigning the 'dj-edit-show' action
CC-4925: Changing User permissions to a higher level ends up with show editing problems

-typo