Check against `null` and `undefined`
Support `Ember::Data::VERSION`

``` ruby
require 'ember/data/source'

Ember::Data::VERSION #=> "0.13"
```
Merge pull request #1019 from tricknotes/version

Support `Ember::Data::VERSION`
Remove unused tasks

Currently ember is managed by `ember-source` gem.
Remove unnecessary comment
Remove unused helper
Remove unused variables
Merge pull request #1021 from tricknotes/remove-unused-tasks

Remove unused tasks
Merge pull request #1020 from tricknotes/remove-unused-valiables

Remove unused valiables
English, do you speak it?
Merge pull request #1028 from bcardarella/grammar

English, do you speak it?
bump ember-dev
Add warning
Merge pull request #1032 from ahawkins/empty-root-warning

Add warning when load request, but not data given
first pass at uncatchable assertions
Fix failing tests due to promise-hidden exceptions and uncatchable assertions
Remove expectAssertion in favor of ember-dev
Merge pull request #1033 from stefanpenner/uncatchable_assert_and_fixes

Uncatchable assert and fixes
Remove bundled jQuery

ref: emberjs/ember-dev#21
Merge pull request #1037 from tricknotes/remove-bundled-jquery

Remove bundled jQuery