tool: change enumeration naming.

Suggesting a name change of isconfigured() return values:
from: CONFIGURED, NOT_CONFIGURED, NOT_SURE
to:   YES       , NO            , MAYBE

Change-Id: I74369c88f149f6c04107019ef66ea42aab5b0405
Signed-off-by: Mooli Tayer <mtayer@redhat.com>
Reviewed-on: http://gerrit.ovirt.org/34046
Reviewed-by: Yaniv Bronhaim <ybronhei@redhat.com>
Reviewed-by: Saggi Mizrahi <smizrahi@redhat.com>