* Remove Handlebars.SafeString usage
* DEV: Support for `import Handlebars from 'handlebars'`;
* FIX: Sprockets was broken when `node_modules` was present
By default the old version of sprockets looks for application.js
anywhere, including in a node_modules folder if this exists
(which it will when we move to Ember CLI.)
- Refactor source_url to avoid using eval in development
- Precompile handlebars in development
- Include template compilers when running qunit
- Remove unsafe-eval in development CSP
- Include unsafe-eval only for qunit routes in development