Added an int-test for user-update-attributes
Added an int-test for user-update-attributes

Added an integration test to validate that passing in no new
attributes to user-update-attributes causes an exception to
be thrown.

Change-Id: I6eba530973cc18834ed08eb91127101d9abb1210
Related-Bug: #1298760

hplustree/trove,zhujzhuo/openstack-trove,cp16net/trove,mmasaki/trove,hplustree/trove,changsimon/trove,changsimon/trove,zhangg/trove,fabian4/trove,openstack/trove,cp16net/trove,mmasaki/trove,cp16net/trove,zhujzhuo/openstack-trove,zhujzhuo/openstack-trove,redhat-openstack/trove,redhat-openstack/trove,redhat-openstack/trove,mmasaki/trove,zhangg/trove,fabian4/trove,changsimon/trove,openstack/trove,fabian4/trove