sendemailsummary.php: correct path to INSTALLDIR

So that we can actually find commandline.inc.

This should have been updated when the files in the EmailSummary tree
where moved down a level into subdirectories.

plugins/EmailSummary/scripts/sendemailsummary.php

@@ -17,7 +17,7 @@
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
 
-define('INSTALLDIR', realpath(dirname(__FILE__) . '/../..'));
+define('INSTALLDIR', realpath(dirname(__FILE__) . '/../../..'));
 
 $shortoptions = 'i:n:au';
 $longoptions = array('id=', 'nickname=', 'all', 'universe');