Adding extra failover options to server configuration

Following Master Slave failover blog from S9 it would be nice to take into account the lack of maxscale features exposed vs MHA

See http://severalnines.com/blog/mysql-replication-failover-maxscale-vs-mha-part-3

failover_candidate_master default 1
failover_failback_delay default 120 sec
failover_slave_lag_delay default 120 sec
failover_http_extra_check_script default http://127.0.0.1:8080/$server/status

this 8080 port would be a local http maxscale listener and that report 404 error when node failed
This would enable multiple maxscale to act against split brain