[WIP] Replace the old admin with the ember admin

Haven't quite gotten this straightened out yet - tests are failing a bit, but the majority of the work is done.

closes #3056

- Remove clientold
- Remove clientold tests
- Cleanup old admin helpers
- Remove old routes from admin and controllers from admin controller
- Comment out / remove old and broken tests
- Cleanup Gruntfile.js, bower.js, package.json etc

Still TODO:

- cleanup / add removed tests
- do we still need countable?