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.

make sure that OBJECT ENCODING returns skiplist for sorted sets, and not raw, so that once we will merge specially encoded sorted sets everything will make sense.

DUMP implemented, RESTORE and MIGRATE fixed. Use zcalloc() instead of zmalloc()+memset() in sds.c when a new string is created with NULL initialization pointer.

fixed memory leak introduced with the previous commit. Many thanks to Pieter Noordhuis for spotting it in no time

Fixed issue #503. MONITOR + QUIT could crash the server, there are actually other interactions that could have the same effect (for instance Pub/Sub).

centralized cluster config file name. Assigned slots in CLUSTER NODES output and in cluster config file.