Improve TestableLock and TestablePriorityScheduler to do deadlock detection

[threadly]

Improve TestableLock and TestablePriorityScheduler to do deadlock detection

[jentfoo]

The only way I can see to do this is to change how we lock. Instead of doing synchronize blocks we would need .acquire() .release() semantics. Although there is nothing wrong with that, I am going to wait on this item for a bit because of the level of effort.

[jentfoo]

This has kind of been put on the back burner for now since the testable facilities of threadly have yet to be seen how valuable they are. There are many other parts that have shown to be much more valuable, so I still have been giving thought as to what the future of the testability side of things may look like.

[jentfoo]

This is no longer relevant since TestableLock and TestablePriorityScheduler has been removed from threadly.