Added length property to Ember.Map
Adds the ability to specify the view class used by the outlet Handlebars helper

Previous to this change, the view class used was always an "OutletView" (Metamorph extension of ContainerView).  This change allows the class to be set while still defaulting to the OutletView
Adding regression test
Make router's render idempotent

This change prevents us from tearing down and recreating a view when
the new view is functionally identical to the old view.

This has important benefits:

 - when you're changing context within a route, the view itself
   remains stable, and the controller has full control over how and
   when to update the data it's presenting to the view
   layer. (Previously, you got a forced re-render immediately whether
   you were ready for it or not.)

 - when you're changing between routes, you can decide to keep the
   prior view in place, and replace it later when you're ready. (Think
   animated transitions between routes.)

This supercedes the proposed changes in PR #2563 (which has already
been reverted).
Clean up pendingDisconnections propertly
Merge pull request #2627 from teddyzeenny/visit-url

Ember testing update url in visit helper
Fix language type
Fix value type

These methods treat `Number` value.
Fix argument name

`decrementProperty` should receive argument as `decrement`.
Fix code comment at `Ember.TextField`

This property is `onEvent`.
Merge pull request #2629 from tricknotes/fix-typo-in-code-comment

Fix typos in code comment
Fix Ember.Test.registerHelper test
Revert "Merge pull request #2577 from machty/bubbling-controller-events"

This reverts commit 05686ccce26808da4a1e1247b131c68cfba15486, reversing
changes made to 7387d6723b5a20395dfd041a67633a6101c2259d.
Fixed small typo
Merge pull request #2639 from machty/revert-controller-bubbling-actions

Revert "Merge pull request #2577 from machty/bubbling-controller-events"
Removed duplicate test for normalizeTuple
Makes partial helper only lookup the deprecated template name if the first try is unsuccessful.
Merge pull request #2641 from intuitivepixel/master

Fixed small typo, and simplified comment.
Merge pull request #2643 from machty/dup-tuple-test

Removed duplicate test for normalizeTuple
Fix docs to use extend instead of create when setting observers