WIP: this will get squashed into previous commit

- change .$resolved to be boolean (true/false), rather than undefined/true
- keep the original promise (do not update .$promise after subsequent instance calls)
- success callbacks gets response (with value as .resource), instead of direct value (this is just
  reverting to the original behavior of $resource)
- docs: reflect these changes
- some style/formatting (reverting trailing white spaces, etc.)