Updated openstack/openstack
Project: openstack/glance  0741c4004af0141d64a2aecc7e3d908638420003
null
Adds TaskStub class

Partial Task patch, Id I4fbadc9a97e3147128c7c733384c7bb50918806f
removed the result and message vars of the Tasks class. However,
the succeed and fail methods were using those to update them
respectively. This patch introduces a new TaskStub class which
enables the PartialTask functionality without looking result
and message attrs of the Task class.

Fixes bug 1284975

Change-Id: I0b406e4662cfd3cb496b71be77ad10a90c178baa