Small fixes.
More test cases fixes.
Refactor how timing code works.

Support scheduling functions, not just testharness test objects.
Always have a dummy t=0 object.

Fixes #224
Merge branch 'fixing-t0-problem'
Fixing test-transform-unit test.
Reverting a stupid change i made in test-compositing-order
Merge pull request #233 from mithro/fixing-t0-problem

Refactor how timing code works.
Reworking test-restart to make more sense.
Adding dummy tests so that none of the tests are in "no-test" state.
Log when the callbacks are called for easier debugging.
Call the callbacks in the same order they where added.
Merge remote-tracking branch 'up/master'
Merge branch 'callback-order'
Merge pull request #236 from mithro/callback-order

Two small fixes (callback order and logging).
Merge pull request #234 from mithro/master

Fixing the currently broken tests.