Delete tests; Created client interface.
Set up new CRUD test to run on a stub.
Picked old tests back out from master.
Created simple one-level-deep CRUD tests on users.
Modified so that RestClient/Service 's update/save methods return domain
objects.

Tests are currently failing, because ApiController isn't implemented.
ApiController now passes the 1-level-deep CRUD tests.
ApiController/RestClient now passes 2-level-deep CRUD tests. Minor bug
about User initially having a null Set<TaskList> is fixed.
All 3-level-deep CRUD tests, despite simple, are passed.