+Address, +Options)Register a redis server without connecting to it. The ServerName
acts as a lazy connection alias. Initially the ServerName
localhost:6379 with no connect options. The
server is used for redis/1 and redis/2
and may be changed using this predicate. Options are
described with redis_connect/3.
Connections established this way are by default automatically
reconnected if the connection is lost for some reason unless a
reconnect(false) option is specified.