updated travis tests README

tests/unit/data/travis/README.md

@@ -10,3 +10,5 @@ The scripts are:
    Compiles and installs the [memcache pecl extension](http://pecl.php.net/package/memcache)
  - [`cubrid-setup.sh`](cubrid-setup.sh)
    Prepares the [CUBRID](http://www.cubrid.org/) server instance by installing the server and PHP PDO driver
+ - [`sphinx-setup.sh`](sphinx-setup.sh)
+   Prepares the [Sphinx](http://sphinxsearch.com/) server instances by installing the server and attaching it to MySQL