post freeze work

Post feature freeze TODO list:

- Redis versioning and releases documentation
- HSETNX, HMGET, HMSET
- zipmaps defragmentation (merge Pieter work)
- Input validation for integer arguments (merge Alex work)
- BLPOP tests, in gereral ability to do multi-client tests in test-redis.tcl
- SETEX (Set + Expire)
- CI (continuous integration testing), with valgrind and different redis.conf
- Virtual Memory proof reading
- Consistency in MULTI/EXEC + AOF. Write the AOF only when EXEC finished.
- Trace/Fix VM bug about assert (see bug2.txt)
- Don't save empty values in .rdb files
- Pub/Sub: rename "class" into "channel"
- SORT BY key->field and GET key->field
- Create a Redis Google Group about Redis client lib. Migrate to new protocol.
- Weeks of stress testing, source coverage tests
- Make redis-tools better to stress test more the VM implementation
- Pattern matching capabilites for Pub/Sub