Ensures RHOS SOS Plugins is installed on all nodes

Fixes: rhbz#1053734
FIxes: rhbz#1131619
Signed-off-by: Gael Chamoulaud <gchamoul@redhat.com>
(cherry picked from commit 0d5836afe088100cdeb99212d831d65c23b2fd14)

Conflicts:
	packstack/plugins/serverprep_001.py

Change-Id: I25c7c066b2f403d6f47787f3f07ac99a53dc6729
Merge "Ensures RHOS SOS Plugins is installed on all nodes" into havana