configfile: sort dict items inserted to config files for consistency.

See comment  one at bug.

Change-Id: I7705b046d993cc08eac6b09a6ebba34bd8986620
Bug-Url: https://bugzilla.redhat.com/show_bug.cgi?id=1127877
Signed-off-by: Mooli Tayer <mtayer@redhat.com>
Reviewed-on: http://gerrit.ovirt.org/31289
Reviewed-by: Nir Soffer <nsoffer@redhat.com>
Reviewed-by: Ondřej Svoboda <osvoboda@redhat.com>
Reviewed-by: Francesco Romani <fromani@redhat.com>
Reviewed-by: Dima Kuznetsov <dkuznets@redhat.com>
Reviewed-by: Dan Kenigsberg <danken@redhat.com>