Reverify no longer requires check tests to re-run

Fix for bug 1339943
Also pulled in some simplifacation from openstack change:
	https://github.com/openstack-infra/config/commit/596de54b92

Note that after a failed gate test, a "recheck" comment will trigger
check tests, while a "reverify" comment will trigger gate tests.
Test reviews show this behavior:
	https://review.trafodion.org/#/c/87/
	https://review.trafodion.org/#/c/88/

Change-Id: Icfd9e70b081f5b98c3e7e11229a8f26e522f1d56
Merge "Reverify no longer requires check tests to re-run"