CLUSTER RESET implemented.
CLUSTER RESET implemented.

The new command is able to reset a cluster node so that it starts again
as a fresh node. By default the command performs a soft reset (the same
as calling it as CLUSTER RESET SOFT), and the following steps are
performed:

1) All slots are set as unassigned.
2) The list of known nodes is flushed.
3) Node is set as master if it is a slave.

When an hard reset is performed with CLUSTER RESET HARD the following
additional operations are performed:

4) A new Node ID is created at random.
5) Epochs are set to 0.

CLUSTER RESET is useful both when the sysadmin wants to reconfigure a
node with a different role (for example turning a slave into a master)
and for testing purposes.

It also may play a role in automatically provisioned Redis Clusters,
since it allows to reset a node back to the initial state in order to be
reconfigured.

darksideofthemoo/redis-histogram,MSOpenTech/redis,maodeyi/redis_lua,MSOpenTech/redis,slfs007/mk-redis,ttuna/msot-redis,Hailei/redis,ramonsnir/redis,spearhead-ea/redis,ksarch-saas/redis,jxwr/redis,ttuna/msot-redis,splitice/redis,himoca/redis,HunanTV/redis,ttuna/msot-redis,ksarch-saas/redis,maodeyi/redis_lua,MSOpenTech/redis,Hailei/redis,ttuna/msot-redis,ramonsnir/redis,spearhead-ea/redis,maodeyi/redis_lua,Hailei/redis,ksarch-saas/redis,slfs007/mk-redis,darksideofthemoo/redis-histogram,splitice/redis,jxwr/redis,spearhead-ea/redis,ksarch-saas/redis,xuzhezhaozhao/redis_reading,MSOpenTech/redis,xuzhezhaozhao/redis_reading,louisliangjun/redis,darksideofthemoo/redis-histogram,xuzhezhaozhao/redis_reading,himoca/redis,xuzhezhaozhao/redis_reading,HunanTV/redis,splitice/redis,HunanTV/redis,louisliangjun/redis,slfs007/mk-redis,himoca/redis,darksideofthemoo/redis-histogram,ttuna/msot-redis,jxwr/redis,ramonsnir/redis,HunanTV/redis,louisliangjun/redis,splitice/redis,Hailei/redis,MSOpenTech/redis,louisliangjun/redis