Experimental synthaway 2

Please **do no** accept this pull request. This is to document a crash in the unit tests with my experimental branch. I currently have no idea what’s causing it. Maybe you can enlighten me: 

The unit test “-testCommitWithTag” crashes early after “-initializeRepository” is being called in “-waitForQueue:” called from “-tearDown”, because the queue is nil. I have tried to track this down, but I am hampered by my understanding of the Xit internals.

This crash does not happen on master.