webadmin : Existing gluster cluster import iptables config

This patch enables iptables rules configuration,
when importing existing gluster cluster configurations

Change-Id: Ib4a391cb1f912c4c052ff183de6463edcad4e0a9
Bug-Url: https://bugzilla.redhat.com/show_bug.cgi?id=1051019
Signed-off-by: Anmol Babu <anbabu@redhat.com>