Updated openstack/openstack
Project: openstack/ceilometer  34db7d95c83a7698732d82820fa17ca8cea6284a

mongo: remove _id in inserted alarm changes

This change ensures that mongodb driver doesn't modify the alarm changes
dictionary when we insert a new alarm changes. To avoid the insertion
of the internal '_id' of mongodb.

Change-Id: I9bcd643c9dc55449141cee94ef6826784e81e4e5