[FEATURE] Essential Skills Coach Improvements

[shurwit]

• [x] Don't show assignment completion/feedback buttons until end of day
• [x] Support HTML body on assignments
• [x] Support linking to resources (eg. video, web link, PDF, text resource...) from dashboard
• [x] Bug fixes
  • [x] Not transitioning to new unit after finishing
  • [x] Streaming video issue - how to refresh user token when streaming through content BB?
  • [x] Streaks shifted by one day