anchor.diff:  #
   # <state> is "start", "end" or "abort"
   # <role> is either "leader" or "observer"
  -# 
  +#
   # The arguments from-ip, from-port, to-ip, to-port are used to communicate
   # the old address of the master and the new address of the elected slave
   # (now a master) in the case state is "start" or "end".
  
positive.code: # When the failover starts, ends, or is aborted, a script can be called in
  # order to perform application-specific tasks to notify the clients that the
  # configuration has changed and the master is at a different address.
  # 
  # The script is called in the following cases:
  #
  # Failover started (a slave is already promoted)
  
negative.code: # Example:
  #
  # sentinel client-reconfig-script mymaster /var/redis/reconfig.sh
  