Also includes RequireJS changes.

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

studio - fixes Sass variable defintion to ensure the older -serif references the proper new -sans-serif variable

typography, SASS import, mixins/extends

studio - sass cleanup: adding in more color variables, proofing box-sizing and older/rougher unit scss

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

studio - tender widget: added compromise of style given iframe and clunky DOM elements that tender is using. meh.

studio - alerts: refactored styles for common content types across UI, got prompts set up and styled, and refactored base template for future prompt/notification/alert use

studio - alerts: converted transition-based animation to keyframe/css animation and added in a demo for a fleeting notification