Renamed 'query' to 'filter', and removed the distinct() method.
Merge branch 'master' into query-cleanup
Completely replace this.last with each query call.

(so we don't have old query info hanging around after multiple calls)
Corrected remove() and store() to treat this.last the same way as the query functions.
Updated unit tests to test the full backend.last object in one shot.

Also corrected the order of arguments so the actual value is first, followed by the expected.
Merge pull request #4 from Morgul/query-cleanup

Query cleanup