Epedev 3.3 ay

committed code includes the following 3.3 tasks

epedev-390: Video controls disappear when you switch datasets in LLB student view
epedev-354: Add AJAX pagination to the Resource Browser
epedev-293: Allow users to include other resources (especially videos) in the slideshows.
epedev-406: Add description box to LLB ancillary materials upload form