Fixes #386, Fixes #415, Fixes #404, Fixes #206: Incorporate default transforms to RESTAdapter

* Created integration test for default DS.Transforms
* Added unit test for models for default DS.Transforms (commented out some of the tests, see #421) from: 8a812c8
* Modified transforms.js to use DS.Transforms namespace
* Modified transforms.js to use fromJSON/toJSON instead of to/from
* Modified serializer to create an instance of DS.Transforms for it's default transformations instead of using the passthrough hack
* Modified transforms.js to have a little bit of logic in boolean transform
Add record unloading support

Add unloadRecord() method to record instance aand to the store.
We also unlaod records when they are deleted and saved.
Maintain order in HasMany when removing and adding to the same collection
use serializeId in RESTSerializer#addBelongsTo
FixtureAdapter calls store.didUpdateAll for findAll
Merge pull request #422 from Mochaleaf/transforms

Incorporate default transforms to RESTAdapter
Initial implementation of embedded load

Inline docs to follow
Refactor DS.Mappable
Changes `json` to `data`

See BREAKING_CHANGES.md for more information
Add a bunch of inline docs to DS.Serializer
Merge pull request #456 from mhelabs/fix_has_many_order

Maintain order in HasMany when removing and adding to the same collection
Fixed jshint
Merge pull request #459 from pangratz/use_serializeId_in_RESTSerializer_addBelongsTo

use serializeId in RESTSerializer#addBelongsTo
Merge pull request #466 from twinturbo/isupdating-fixture-adapter-fix

FixtureAdapter calls store.didUpdateAll for findAll
Revert "Merge pull request #459 from pangratz/use_serializeId_in_RESTSerializer_addBelongsTo"

This reverts commit 4b8bb237ff85b9141427e5ec115ef33509d20580, reversing
changes made to 9f4d714c9b6ba4645ed854eb75064b6d224ab573.
Clear test timer on observer execution

Fixes the build when run within the browser.
Number object doesn't have a search method
- If your REST service returns a Date as a number, the deserialization
  fails because the transform fromData tries to use search on a number
Added test for tranforming a timestamp (number) into a Date
Allow belongsTo to specify inverse
Handle some create and update errors in the REST adapter.

* 422 Unprocessable Entity

  Transitions the record to the invalid state. Assumes
  the server has responded with `{errors: {...}}` and
  sets them on the record.

* All other status codes

  Transitions the record to the error state.

This is limited to only single, non-bulk creates/updates.