In the past, the result of template compilation would be stored directly in `Ember.TEMPLATES`. Following the move to more modern ember-cli-based compilation, templates are now compiled to es6 modules. To handle forward/backwards compatibility during these changes we had logic in `discourse-boot` which would extract templates from the es6 modules and store them into the legacy-style `Ember.TEMPLATES` object.
This commit removes that shim, and updates our resolver to fetch templates directly from es6 modules. This is closer to how 'vanilla' Ember handles template resolution. We still have a lot of discourse-specific logic, but now it is centralised in one location and should be easier to understand and normalize in future.
This commit should not introduce any behaviour change.
We were sharing `Discourse` both as an application object and a
namespace which complicated things for Ember CLI. This patch
moves raw templates into `__DISCOURSE_RAW_TEMPLATES` and adds
a couple helper methods to create/remove them.