set parents on new records in cached update
replace Ember.run.later with setTimeout for tests

[fixes #8] setTimeout's behavior is more predicable, and the tests now
ensure that AJAX calls take 5ms, so waiting 10ms to test for post-cache
behavior is safe.
README should show master status
ensure that AJAX calls are not made after tests pass
Merge pull request #1 from jclem/master

Update