There is a lot of test framework code duplicated between
tracker-miners.git and tracker.git. This has been a problem since
tracker-miners.git was split out from tracker.git.

Now, the majority of the test framework lives in tracker.git and
is installed as a private Python library, which is used by the
tests in this repository.

With this change, the tests are launched via D-Bus auto activation
rather than being explicitly launched by the tests  Logging is much
improved. See HACKING.md in tracker.git for details.