Remove feature flags for 'ember-routing-loading-error-substates'.
Remove feature flags for 'ember-runtime-sortBy'.
Remove feature flags for 'container-renderables'.
Remove feature flags for 'link-to-non-block'.
Remove feature flags for 'reduceComputedSelf'.
Components are lazily looked up.
Fix incorect removal of 'ember-routing-loading-error-substates'.
[FEATURE ember-testing-routing-helpers]

Adds `currentRouteName`, `currentPath`, and `currentURL` testing helpers.
Merge pull request #3711 from rjackson/add_route_testing_helpers

[FEATURE ember-testing-routing-helpers]
Merge pull request #3787 from rjackson/remove_stable_feature_flags

Remove feature flags that are included in 1.2.0.
Merge pull request #3764 from abuiles/add_link_to_handlebars_checkbox

[DOC] Add missing link to handlebars.helpers.input in Ember.Checkbox.
Ember.Object.create now takes `undefined` as an argument.

Fixes #3701.
Merge pull request #3782 from twokul/ember-object-create-undefined

Ember.Object.create now takes `undefined` as an argument.
[FEATURE ember-testing-triggerEvent-helper]

Adds `triggerEvent` testing helper to allow triggering of arbitrary
events on an element.
Merge pull request #3792 from rjackson/trigger_test_helper

[FEATURE ember-testing-triggerEvent-helper]
Merge pull request #3480 from Lowest0ne/remove-redundant-assignment

remove redundant assignment of isDestroyed
short-circuit inner loop if no properties are present.
Update to latest RSVP (80cec268).

A few of the changes:

* Added `Promise.cast`
* Added `Promise.finally`
* Added `RSVP.on('error', callback)`.

See full changes [here](https://github.com/tildeio/rsvp.js/compare/ae4abbccea971a7a7a0437d8275b6c5f1f21ff4c...80cec268a5ef91273b2dd6cd83c3d3d4f4d427df).
Merge pull request #3784 from rjackson/update_rsvp

Update to latest RSVP (80cec268).
[BUGFIX] Register a default RSVP error handler.

This will significantly improve the users experience when debugging
errors thrown in promises as they will now be logged to the console in
development.