power_on/power_off in compute manager to use uuids
power_on/power_off in compute manager to use uuids

Related to blueprint internal-uuids. Changes power_on and power_off of instances
to use uuids. Also, fixes a test for get_actions to be more accurate. Later a
migration will need to be written for instance_get_actions to use uuids instead
of ids.

Change-Id: Id0896f4bf3f0c64a77ac9c421bad702073f2fc50

n0ano/gantt,n0ano/gantt