Merge all changes from databases/redis-devel to databases/redis.
<ChangeLog>
Redis 3.0 release notes
=======================
--[ Redis 3.0.0 ] Release date: 1 Apr 2015
>> What's new in Redis 3.0 compared to Redis 2.8?
* Redis Cluster: a distributed implementation of a subset of Redis.
* New "embedded string" object encoding resulting in less cache
misses. Big speed gain under certain work loads.
* AOF child -> parent final data transmission to minimize latency due
to "last write" during AOF rewrites.
* Much improved LRU approximation algorithm for keys eviction.
* WAIT command to block waiting for a write to be transmitted to
the specified number of slaves.
* MIGRATE connection caching. Much faster keys migraitons.
* MIGARTE new options COPY and REPLACE.
* CLIENT PAUSE command: stop processing client requests for a
specified amount of time.
* BITCOUNT performance improvements.
* CONFIG SET accepts memory values in different units (for example
you can use "CONFIG SET maxmemory 1gb").
* Redis log format slightly changed reporting in each line the role of the
instance (master/slave) or if it's a saving child log.
* INCR performance improvements.
>> Refactoring changes (no new features nor bug fixes)
* Blocking operations full refactoring (blocked.c)
* Client output buffer memory tracking refactored.
</ChangeLog>
