Revert "Remove startup check from devstack"
Revert "Remove startup check from devstack"

This reverts commit 4a1a6b3766b7cd63afff36307a8044cf3b848a31. It didn't
improve the situation, and at least it's failing early.

Conflicts:
	devstack/plugin.sh

Change-Id: Idf16037e6a3bbc7f915e12827348eda663721d5e

openstack/zaqar,openstack/zaqar,openstack/zaqar,openstack/zaqar