OS-247: show SCHEDULING and BLOCK_DEVICE_MAPPING

We weren't putting instances in the task_states SCHEDULING or
BLOCK_DEVICE_MAPPING. Although these transitions aren't required for
correctness, they're useful data points when measuring performance.

Also backported the _copy_instance test in test_api.py from havana/1.5
to grizzly/1.5.

Change-Id: Ic0e3955d3c54977f9412aeba68c7000c3cbfad1e
Merge "OS-247: show SCHEDULING and BLOCK_DEVICE_MAPPING" into grizzly/1.5
Merge 'OS-247: show SCHEDULING and BLOCK_DEVICE_MAPPING' from grizzly/1.5

Conflicts:
	cobalt/tests/test_api.py

Change-Id: I08fd4bc4ad72e0843ce3900b8500cbe92de1be92