get rid of unused function chooseVideo
Reorganize Backbone structure to be more MVC-like

Fix the UI for the "wheel", make it into a scrollable list.
Currently have selection for playlist working. Need to get
selecting a video working, and then work on rewiring the
Random Video button.
Separate models and views to own files

Also got video selection working. Just need to fix the random button now.
changed how VideoChooser is constructed
started inferring categories/subcategories
Some Cat/Subcat work

Updated Cat/Subcat model construction
Consolidated render logic into ListView
got video selection working
updated list styles, decomposed click handler to ListView
refactored, created VideoInfoView
got the random video button working
get rid of placeholder videoInfo html
highlight selected items for random video