This is to help with the migration to Ember CLI. In the current running
version of Discourse everything should be the same as before, just with
a few extra files that are not used. However, using Ember CLI this can
be installed as an Ember addon.
Co-Authored-By: Jarek Radosz <jradosz@gmail.com>
We weren't using this very much and introduces a dependency between
discourse-common and discourse which makes moving to yarn workspaces
more difficult.
In the future we might user ember-addons properly but for now it's
easier to move the code into discourse-common.
Note the old folder is still there because at least one plugin was still
requiring the old files. It will be removed in the future.
