Make sure we don't reuse Augeas objects in ovirt.node.config

If multiple admin sessions were opened, changed values which
relied on Augeas (DNS and NTP settings, principally) did not
reflect changes between them without quitting the UI. Force a
reload of cached Augeas values so it properly updates.

Change-Id: I3c91839c4dca91fed47d457bdb8a1f712c172822
Bug-Url: https://bugzilla.redhat.com/show_bug.cgi?id=985228
Signed-off-by: Ryan Barry <rbarry@redhat.com>