Response from write actions should update cache always, including when values no longer exist

[dannynelson]

if we make a request like this:

POST [{id: 1, name: 'Danny'}, {id: 2, name: 'Max'}]

and the server responds like this:

[{id: 1, name: 'Danny'}]

we should delete the resource that wasn't returned, {id: 2}, from the cache.