Add new "activeusers" field containing last month active users in registration data

Requirements Ability to edit the test site's config.php file and control the deployed code. MDL-68060 also integrated. Please contact David Mudrak prior the test to make sure that the staging server is ready to accept these new indicators. Test Set up an existing site installation WITHOUT this patch (such as latest weekly build from the last week). Register the site with a staging/test sites directory (ask David Mu for credentials) Update the site to to the latest integration.git version WITH the patch. TEST - visit the site registration page and check that two new indicators are highlighted (see attached screenshot-1.png) and require the admin's attention. Update the site registration by re-submitting the form. TEST - check that the site registration was succesfuly updated Run the site registration update scheduled task. TEST - check that the site registration update task was succesfuly executed TEST - check with David Mu that the information is available in the sites directory database