Deep-copy not always possible.

In working with cinder it appears that at last
cinder is using objects which can not be deep
copied (sqlalchemy objects) and which actually
cause the deepcopy routine to fail. To get
around this avoid the deepcopy until proven
its really needed.

Change-Id: Ia7b7c49e82c2151351cc0f78ecb1531c35540652
Merge "Deep-copy not always possible."