engine_page: display url/port only on availble

Do not show URL and PORT on status page if we don't have
these data available.

Change-Id: If2d64a3d0c3530432544afbf3fe8a8155a2698d2
Bug-Url: https://bugzilla.redhat.com/show_bug.cgi?id=1057453
Signed-off-by: Douglas Schilling Landgraf <dougsland@redhat.com>