Cleanup fixup.

	- VM instance cleanup steps are skipped, if VM instance was deleted before cleanup.
	- Line 639: Nova delete argument changed from "Instance name" to "Instance id".
	- Line 647: Nova volume-delete argument changed from "Volume name" to "Volume id", deletion is performed only if this volume still exists in moment of performing "volume-delete".

Conflicts:
	smoketest/00-deploy-nova-vm.test