PHP extension for interfacing with Redis

This extension provides an API for communicating with Redis servers.

phpredis 3.1.3RC1

This release contains two big improvements:
1. Adding a new printf like command construction function with additionaly format specifiers specific to phpredis.
2. Implementation of custom objects for Redis and RedisArray wich eliminates double hash lookup.
Also many small improvements and bug fixes were made.

* A printf like method to construct a Redis RESP command [a4a0ed, d75081, bdd287, 0eaeae, b3d00d] (Michael Grunder)
* Use custom objects instead of zend_list for storing Redis/RedisArray [a765f8, 8fa85a] (Pavlo Yatsukhnenko)
* Make sure redisCluster members are all initialized on (re)creation [162d88] (Michael Grunder)
* Fix Null Bulk String response parsing in cluster library [058753] (Alberto Fernández)
* Add hStrLen command [c52077, fb88e1] (Pavlo Yatsukhnenko)
* Add optional COUNT argument to sPop [d2e203] (Michael Grunder)
* Allow sInterStore to take one arg [26aec4, 4cd06b] (Michael Grunder)
* Allow MIGRATE to accept multiple keys [9aa3db] (Michael Grunder)
* Allow using numeric string in zInter command [ba0070] (Pavlo Yatsukhnenko)
* Use crc32 table from PHP distro [f81694] (Pavlo Yatsukhnenko)
* Use ZVAL_DEREF macros for dereference input variables [ad4596] (Pavlo Yatsukhnenko)
* Add configureoption tag to package.xml [750963] (Pavlo Yatsukhnenko)
* Fix read_timeout [18149e, b56dc4] (Pavlo Yatsukhnenko)
* Fix zval_get_string impl for PHP5 [4e56ba] (Pavlo Yatsukhnenko)
* Fix Redis/RedisArray segfaults [be5c1f, 635c3a, 1f8dde, 43e1e0] (Pavlo Yatsukhnenko)
* Fix memory leak and potential segfault [aa6ff7, 88efaa] (Michael Grunder)
* Throw exception for all non recoverable errors [e37239] (Pavlo Yatsukhnenko)
* Increase read buffers size [520e06] (Pavlo Yatsukhnenko)
* Better documentation [f0c25a, c5991f, 9ec9ae] (Michael Grunder)
* Better TravisCI integration [e37c08] (Pavlo Yatsukhnenko)
* Refactoring (Pavlo Yatsukhnenko, Michael Grunder)