Destroying the store now:

- unload's all Records
- unload's all RecordArrays
- destroy's all records (so life cycle hooks get called for cleanup)
- destroy's all RecordArrays

Unloading a record now:
- is allowed, unless the record is inflight. (previously it was disallowed for all dirty states)

also, now once a record has been destroyed attempts to unload it will be
black holed
Use Ember getter instead of accessing the property directly.
lock server while compiling assets
Merge pull request #1752 from fivetanley/grunt-locking-server

lock server while compiling assets
Merge pull request #1714 from stefanpenner/cleanup_when_store_destroys

Destroying the store cleanups up after itself:
Update ember version to 1.4.0
Merge pull request #1754 from tricknotes/update-ember-to-1.4.0

Update ember version to 1.4.0
Document required structure for DS.InvalidError
Merge pull request #1756 from Kerrick/patch-1

Document required structure for DS.InvalidError
1.0.0-beta.6 changelog
Release 1.0.0-beta.7
Post release VERSION bump
1.0.0-beta.7 CHANGELOG
actually update version for post-release version bump
Merge pull request #1749 from vseventer/master

Use Ember getter to retrieve the RESTAdapter headers.
fix small typo in CHANGELOG.md
Remove duplicate changelog entry.
Merge pull request #1761 from ugisozols/remove_dup_changelog_entry

Remove duplicate changelog entry.
Improve store docs to use container lookup not concrete class
Merge pull request #1770 from alexspeller/improve-store-docs

Improve store docs to use container lookup not concrete class