Log when task is not configured properly
Log when task is not configured properly

Currently we fail silently when a task is not configured properly.
Silent failures make things particularly hard to understand when behaviour
does not match expectations.

Change-Id: Ib4d8f2bdf3299caaf91bd5a99c6a014f87143e4a
Closes-bug: 1532243

openstack/glance,rajalokan/glance,stevelle/glance,openstack/glance,rajalokan/glance,stevelle/glance,openstack/glance