Updated openstack/openstack
Project: openstack/ceilometer  b89ebc6425523a3ec1d6212d53e5e6a9442188f3
null
Replace tests.base part6

It is the sixth step to replace using ceilometer.tests.base with
openstack.common.test.
In this patch is changed for using
openstack.common.test and added needed fixtures in
test classes.
Added in ceilometer.tests.db code from ceilomete.tests.base
because ceilometer.tests.base will not be used in the future.

Change-Id: I3cacca4eff19eae8874decd892ab1225f95cfee9