add language string

lang/en/theme_unige.php

@@ -8,6 +8,7 @@ defined('MOODLE_INTERNAL') || die();
 $string['pluginname'] = 'UNIGE';
 $string['choosereadme'] = 'University of Geneva Moodle theme';
 $string['region-side-pre'] = 'Right';
+$string['region-side-left'] = 'Left';
 
 $string['my-courses'] = "My courses";
 $string['course-catalogue'] = "Course catalogue";