added minimal cluster section in INFO output. This is only useful to check if the instance is or not configured as a cluster node, all the other informations are accessible using the CLUSTER command.

evaluate cluster state after config load. Still bugs in the slot allocation after nodes config load to fix.

when loading config set the ping/pong timestaps to the current value. Even a node in FAIL state can be accepted again if there are no slaves for this node so election was not possible

fixes to configuration loading and saving. However there is to still fix the logic for reconnection/behavior of nodes after a restart.