Update to gear 0.2.0.

The internal data structure of the server queue changed.

Change-Id: I280a671577d2247b315174f543dfb2ff8b7d51f4
Reviewed-on: https://review.openstack.org/31997
Reviewed-by: Clark Boylan <clark.boylan@gmail.com>
Approved: James E. Blair <corvus@inaugust.com>
Tested-by: Jenkins