Add functional recreate test for live migration pre-check fails
Add functional recreate test for live migration pre-check fails

This adds a functional test to recreate bug 1712411 where
the allocations created against the destination node are not
cleaned up by conductor when a MigrationPreCheckError happens
and a rechedule to another host happens (or max retries are
exceeded which is the case here with only two computes).

Change-Id: Ieee45521c7e362b7dd053b20d3c39dea330ca080
Relatd-Bug: #1712411

phenoxim/nova,mikalstill/nova,klmitch/nova,openstack/nova,rahulunair/nova,gooddata/openstack-nova,klmitch/nova,mikalstill/nova,gooddata/openstack-nova,rahulunair/nova,mahak/nova,openstack/nova,openstack/nova,klmitch/nova,klmitch/nova,mikalstill/nova,gooddata/openstack-nova,mahak/nova,rahulunair/nova,phenoxim/nova,gooddata/openstack-nova,mahak/nova