Log Message:
Update php-memcache to 2.2.7. (leaf package)

- PHP 5.4 compatibility
- Fixed return value error get_host_port_from_server().
- Fixed PECL Bug #16672 (memcache.php doesn't support unix socket)
- Fixed pecl bug #19374 (memcache.php throws Notice: Undefined index: VALUE
  when viewing expired items)