Wait for EditPostVC revision creation

- This test fails due to Reader interference in the rest of the app when run individually

- Another method with be used to remedy

- Add comments to ReaderTest to clarify
Separate lock for EditPostVC

- When this test is run while the app launches, the Reader data saves call ATHNotify() and prematurely signals the ATHSemaphore.

- Avoid using self in init for EditPostVC.