webadmin: check up server in gluster cluster guide me

While showing the Guide Me popup for a gluster supported
cluster which already contains some hosts in it,
'Add Another Host' and 'Select Host' action will be shown
only if there is a host in Up status.

Change-Id: I0cea3a3c2a64eca78740d921680faeeb0c5473c7
Bug-Url: https://bugzilla.redhat.com/906703
Signed-off-by: Kanagaraj M <kmayilsa@redhat.com>