* updating vendor files
* updating class syntax (to new FA-based classes) for all UI elements
* correcting broken tests

SASS compilation variable conventions update, focusing on basic colors, baseline variable usage for padding and margins, ui-depth extends, along with other small fixes. The intent with this is to not have any user-facing impact, and instead move us closer toward having files that use our newer sass conventions.

* removing unused font-family-centric Sass variables
* removing unused graphic images and Sass references
* clean up of style removal fallout

* moving font-size to use @include font-size() mixin
* re-organizing vendor reset styling into _vendor.scss override rather than _reset.scss
* initial rule re-organization and minor line-height tweaks

cleanup of unit, container, and xblock sass; added modules and layout sass; publishing states and actions on new unit

STUD-1312

Studio: revising .fake-link utility class to use Sass placeholder and syncing commenting style

LMS: updating Sass ui-disabled placholder syntax and creating utility is-disabled class

Studio: adding in basic action Sass placeholder for use in enabling/disabling UI

Studio: applying action Sass placeholder to publish/create-draft Unit view actions

STUD-1497

STUD-1306

styling for recursive xblock rendering structure to be used in the container page, pulling from general xblock styles in a separate file.

Also includes RequireJS changes.

Fixes bugs:
STUD-755, STUD-152, STUD-700, STUD-699