document some ember-testing helpers
fix some consistencies mistakes

I don't know if the remainings `control` terms are legits or not, so I didn't touch them. Please let me now if all `control` should be renamed to `component`. cc/ @wycats
Show `beforeModel` and `afterModel` in API Route docs
Merge pull request #2883 from bradfol/route-docs

Show `beforeModel` and `afterModel` in API Route docs
Merge pull request #2879 from sly7-7/patch-1

fix some consistencies mistakes
Update Handlebars version.
Merge pull request #2845 from fivetanley/document-ember-testing

document some ember-testing helpers
Use Ember setter to set Ember.Route controller.
Support grouping option for Ember.Select using optgroup
Merge pull request #2465 from tricknotes/optgroup-for-select

Support grouping option for Ember.Select using optgroup
Switch from unbind to off for router location events
Merge pull request #2885 from gdub22/router-location-unbind

Switch from unbind to off for router location events
small typo in ember evented comments
Merge pull request #2891 from izhan/doc_tweak

small typo in ember evented comments