STUD-815

Studio: revises CSS reference/pipeline architecture for better organization, reduced redundancy, and to handle IE9 selector limits

Previously the file upload dialog was PDF- and textbook-specific. The
changes are adding parameters to the FileUpload model for the file
type, and adding an onSuccess callback to the UploadDialog view. Also
moved upload-specific SASS into its own file.

Studio: adds in new Sass file for Studio-specific
xmodule presentation and removes full screen control
from video alpha display UI.
Adds jasmine test for subtitles scroll.
Adds tests for caption change height functionality.
Uses gettext wrapper.
Fixes caption change height functionality.
Removes IS_CMS, isCms flags.

typography, SASS import, mixins/extends

This allows us to a) compile the coffeescript and sass from xmodules
using the new out-of-band method and b) reload xmodule static content
whenever it changes, which should make devs much happier.

studio - resolved z-index issue with release date modal and JQUI timepicker + conslidated all vendor styling overrides/extensions

studio - sass cleanup: local merge with master and small comment/organization tweaks to variables and base-styles

studio - Sass Cleanup: moved all page/view specific css to their own views and created forms specific sheet

The scss junk comes from trying to sync w/ several branches. I believe
it's right but mostly unnecessary (surprised it showed up).
Debugged the merge w/ cms-master
Fixed grace period to be absolute time difference not a date on the
client side.