Implemented Memcached

Fixes #1

- Added Memcached server via OPSCode cookbook
- Added PHP Extension for Memcache

    vagrant@precise64:~$ telnet localhost 11211
    Trying 127.0.0.1...
    Connected to localhost.
    Escape character is '^]'.
    version
    VERSION 1.4.13
    quit
    Connection closed by foreign host.

    vagrant@precise64:~$ php -i | grep memcache
    /etc/php5/cli/conf.d/memcache.ini,
    memcache
    memcache support => enabled
    memcache.allow_failover => 1 => 1
    memcache.chunk_size => 32768 => 32768
    memcache.compress_threshold => 20000 => 20000
    memcache.default_port => 11211 => 11211
    memcache.hash_function => crc32 => crc32
    memcache.hash_strategy => consistent => consistent
    memcache.lock_timeout => 15 => 15
    memcache.max_failover_attempts => 20 => 20
    memcache.protocol => ascii => ascii
    memcache.redundancy => 1 => 1
    memcache.session_redundancy => 2 => 2
    Registered save handlers => files user memcache