webadmin: GuideMe Datacenter does not pass OverrideFirewall

- Added passing OverrideFirewall in onAddHost() in DataCenterGuideModel

Change-Id: I4f7adc538204ab578fe3719949d54e6ad7e3a65c
Bug-Url: https://bugzilla.redhat.com/show_bug.cgi?id=1069847
Signed-off-by: Alexander Wels <awels@redhat.com>