Don't bother with Ember.run.once, as we can detect an impending flush
by inspecting the size of the local queue of _deferredTriggers

This should mitigate some costly run-loop pressure.

Inspired to help with: https://github.com/ebryn/backburner.js/issues/51
another quick fix, which should reduce run-loop pressure.
DS.store#filter should always return a DS.ArrayPromise
Merge pull request #1522 from bmac/filter-promise-array

store.filter should always return a FilteredRecordArray
make inverse error more user friendly
Merge pull request #1609 from igorT/igor/inverse_error_message

make inverse error more user friendly
attars with options should allow for key option
Merge pull request #1612 from tchak/attrs-options-key

attars with options should allow for key option
fixed behaviour of store.all() in combination with store.unloadAll() which caused elements to stay in the RecordArray, even if they should have been removed. ref #1611
Clean up the DS.Store docs
Merge pull request #1618 from bmac/store-docs

Clean up the DS.Store docs
Enable building on Windows.

Updates `ember-dev` to 87bc398.

Thanks to @brzpegasus for tracking this down!
Merge pull request #1619 from rjackson/enable_building_on_windows

Enable building on Windows.
Update the DS.Adapter documentation
Merge pull request #1617 from bmac/adapter-docs

Update the DS.Adapter documentation
add DS.Errors object
Update copyright year.
Merge pull request #1620 from rjackson/update_year

Update copyright year.
Clean up the DS.FixtureAdapter docs
Merge pull request #1621 from bmac/fixture-adapter-docs

Clean up the DS.FixtureAdapter docs