Fix syntax and linting errors in JS.
Refactor API endpoints for exercise and attempt logs to be more RESTful.
Set up backbone models to use URLs in place of doRequest.
Add method to update global exerciseData object on ExerciseDataModel change.
Fix to only retrieve last max ten records in attempt_log GET request.
Partial refactoring of exercise code into Backbone views.
Merge branch 'backbone' of https://github.com/rtibbles/ka-lite into backbone

Conflicts:
	kalite/distributed/static/js/distributed/exercises.js
Initial integration of exercise's Backbone models into its views.