Upgrade from 5.0-rc3 to 5.0-rc4.

<ChangeLog>

Upgrade urgency

HIGH: Many non critical but important issues fixed.
CRITICAL for Stream users: Many important bugs fixed.

Fixes:

• A number of fixes related to Streams: stability and correctnes.
• Fix dbRandomKey() potential infinite loop.
• Improve eviction LFU/LRU when keys are created by INCR commands family.
• Active defragmentation is now working on Redis 5.
• Fix corner case in Redis CLuster / Sentinel failover, by resetting the disconnection time with master in a more appropriate place.
• Use a private version of localtime() to avoid potential deadlocks.
• Different redis-cli non critical fixes.
• Fix rare replication stream corruption with disk-based replication.

Improvements:

• Sentinel: add an option to deny online script reconfiguration.
• Improved RESTORE command.
• Sentinel command renaming: allows to use Sentinel with Redis instances that have non standard command names.
• CLIENT ID and CLIENT UNBLOCK.
• CLIENT LIST now supports a TYPE option.
• redis-cli --cluster now supports authentication.
• redis-trib is now deprecated (use redis-cli --cluster).
• Better slaves output buffers efficiency.
• Faster INFO when there are many clients connected.
• Dynamic HZ feature.
• Improvements in what the MEMORY command is able to report.
• Add year in log. (WARNING: may be incompatible with log scraping tools)
• Lazy freeing now works even when values are overwritten (for instance SET).
• Faster ZADD when elements scores are updated.
• Improvements to the test suite, including many new options.

</ChangeLog>