This reverts commit 2c7906999a.
The changes break some things in local development (putting JS files
into minified files, not allowing debugger, and others)
This reverts commit ea84a82f77.
This is causing problems with `/theme-qunit` on legacy, non-ember-cli production sites. Reverting while we work on a fix
This is quite complex as it means that in production we have to build
Ember CLI test files and allow them to be used by our Rails application.
There is a fair bit of glue we can remove in the future once we move to
Ember CLI completely.