First cut at resource deletion. Delete is implemented as a special
built in method present on every resource. Internally, it is
implemented at the method dispatcher level similar to the existing
stop/exit mechanism.

The delete exits the method dispatched and removes all keys
associated with the instance in Redis. However, delete has some
special characteristics noted here:

- Delete always completes asynchronously from the viewpoint
  of a resource proxy. This is because the delete itself
  removes the keys normally needed to respond to a method.

- Delete only deletes all the keys if it is the last copy of
  that instance currently running. Otherwise, that instance
  instance simply exits and repushes the delete token onto
  the method queue for the next copy to handle.

TODO:
- Tests
- Class resource deletion
- Supervisor support
Added test for deleting an instance.
Cleaned up debug logging.
We aren't using mocha in the LiveResource tests, so remove it
from the test_helper.rb.
Change warn log to debug in delete_instance when there are
still instances running.
Simplified event notification on resource registration. We were getting
"updated" events on resources when new instances of resources were
created but nothing was actually changed about them. In this case, we
really just want to see a started event for the new instance. Now
we only generate a "created" event the first time an instance is
registered and we only generate an "udpated" event when a previously
registered resource has new methods or attributes.

Fixed some tests this was affecting along with some general test
clean-up.
Make default test task run both resource and supervisor tests.

Use "resource_test" or "supervisor_test" to run them individually.
Fix warnings in supervisor code.
Fix bug in resource deleted? method. @dispatcher was spelled
incorrectly, resulting in the method always returning false.
Supervisor support for resource deletion. Deleted resources are
removed from the supervisor's worker list and will never be
restarted.