List legacy and current PHP drivers in 3.0 compat table

This table is included in the current SCRAM documentation, in addition to the older 3.0 release notes, so it makes sense to mention the current PHP driver here.

Author: jmikola

source/includes/list-table-3.0-driver-compatibility.rst

@@ -23,7 +23,8 @@
      - `1.0.0 <https://metacpan.org/release/MongoDB>`__
 
    * - :ecosystem:`PHP </drivers/php>`
-     - `1.6 <http://pecl.php.net/package/mongo>`_
+     - `ext-mongo 1.6 <https://pecl.php.net/package/mongo>`_,
+       `ext-mongodb 1.0 <https://pecl.php.net/package/mongodb>`_
 
    * - :ecosystem:`Python </drivers/python>`
      - `2.8 <https://pypi.python.org/pypi/pymongo/>`_