Allow FakePower to return node objects power_state

Remove hard coded return from node FakePower.get_power_state.
Modify set_power_state to change node objects power state.
This patch will allow for deploys with the Fake driver.

Correct issue in conductor manager where it was passing node_id
where drivers were expecting node_obj.

Change-Id: If0911e50c48ad03aa29f4fd708da8f376c823821
Merge "Allow FakePower to return node objects power_state"