Tor has a controller command, TAKEOWNERSHIP, and a configuration option,
__OwningControllerProcess, that work together to ensure Tor shuts down
when the controlling process dies and/or disconnects from the control
port. By using them we can avoid creating runaway Tor processes that
have to be killed with hacks.

Patched jtorctl to pass more information about circuit events to the
controller to help us debug connection problems.

This may have been the cause of bug #69. Removed the wait-for-shutdown
code in DroidtoothPlugin that was added to attempt to avoid that bug.