Added length property to Ember.Map
Use isNone to check tag name
Added API docs for 'needs' property of controller
make use of Ember.isNone explicit in Ember.isEmpty
additional Controller#needs documentation
Adjust wait time to tick next run loop for more browsers
Kepp timers order
Reduce late time to less than resolution capability of `setTimeout`

To test behavior for browsers that has long resolution capability.
Force downcase tag name for IE8
Use stub `Object.create` for IE8

It couldn't treat property descripters.
Skip Object.getOwnPropertyDescriptor only IE8

Because of broken.
Fix to use `Ember.ArrayPolyfills.forEach` for IE8

IE8 has no method `Array.prototype.forEach`.
Merge pull request #2520 from tricknotes/object-create

Use stub `Object.create` for IE8
Merge pull request #2518 from tricknotes/force-downcase-for-ie8

Force downcase tag name for IE8
Merge pull request #2521 from tricknotes/skip-get-own-property-descriptor

Skip Object.getOwnPropertyDescriptor only IE8
Merge pull request #2519 from tricknotes/for-each

Fix to use `Ember.ArrayPolyfills.forEach` for IE8
Merge pull request #2514 from tricknotes/keep-timers-order

Fix to keep timers order
convert bools to flags so it is easier to add new ones
Merge pull request #2515 from tricknotes/set-long-wait-time

Adjust wait time to tick next run loop for more browsers
Merge pull request #2509 from raulbrito/refactor-isNone

make use of Ember.isNone explicit in Ember.isEmpty