Change variable name mode to output_mode.

 * jeepyb/config/openstackwatch.ini-sample

Change-Id: I07a4952db47be100a636486f66811049465b2343
Reviewed-on: https://review.openstack.org/26529
Reviewed-by: James E. Blair <corvus@inaugust.com>
Approved: Clark Boylan <clark.boylan@gmail.com>
Reviewed-by: Clark Boylan <clark.boylan@gmail.com>
Tested-by: Jenkins