[WIP] fix chef-client to work when cluster is down (bnc#900964)

We need chef-client to work on a cluster node even when openais is down,
so that Chef can restart openais.  The start_handler was carelessly
checking for maintenance mode in a way which assumed openais was up.

This *should* help with [bnc#900964](https://bugzilla.suse.com/show_bug.cgi?id=900964) but we need to test that.