By default Redis refuses writes with an error if the latest BGSAVE failed (and at least one save point is configured). However people having good monitoring systems may prefer a server that continues to work, since they are notified that there are problems by their monitoring systems. This commit implements the ability to turn the feature on or off via redis.conf and CONFIG SET.

Client output buffer limits: configuration of parameters for the different classes of clients implemented.

It is now posible to flush all the previous saving points in redis.conf by using a save directive with a single empty string argument, like it happens for CONFIG SET save.

AOF fileds in the global server state, and define names, renamed with more consistent names. More work to do.

It is now possible to disable password authentication via CONFIG SET. Thanks to Jan Oberst. This closes issue #171.

Added a configuration directive to allow a user to specify the
permissions to be granted to the Unix socket file.  I followed
the format Pieter and Salvatore discusses in issue #85 (
https://github.com/antirez/redis/issues/85).

INFO commandstats section reset with config resetstat, a new microseconds per call field, and a few other minor things

added noeviction policy to redis maxmemory. ZSCORE removed from the list of commands that can't be called when we are low on memory, this command was added in the past for a stupid error.

Now it is possible to use quoted strings in the redis.conf file accordingly to the sdssplitargs() function capabilities.