add CRUD for multiple choice answers
allow answers to be submitted for mc questions
missing commas in json
typo, existant->existent
ensure multiple choice answers are valid for their question
mark trigger as stable
Merge branch 'master' into feature/multiple-choice-answers

Conflicts:
	backend/src/backend/questions/models.py
add question_group to question & allow filtering by question_group
opps -- remve .swp file
give travis ci a shot
correct environmental variables for travis ci
add build status link
use build status for upstream branch
test 404s on link uris
another 404 link test
Merge pull request #26 from waltaskew/feature/multiple-choice-answers

In which we add multiple choice questions to our supported question types