Fixes #6287: Remove V1 API entirely.

This commit removes the existence of the V1 API by moving some controllers
to pure V2 API controllers and removing other, unused API controllers
and their corresponding tests.
Fixes #3584: Enable all tests to be run.

During the enginification process, tests were turned on one by one
and in the process some were left out. This changes the test task
to run all tests in the spec/ and test/ directories and fixes
those that haven't been run since engification.