Merge pull request #1 from sfresk/master

Fix for delete method
Bump version for Sean Fresk's delete fix.
Removed TODO note about PUT, POST, DELETE.
Bug fixes mostly around write methods.

Set content-type header from serializer mime setting.

Make meta getter optional (put does not return this in some apis).

Add stub (unfinshed) for header based auth in async adapter.
Role version to 0.99.5