MDL-9111: Changed to "Back to groups"

group/assign.php

@@ -176,7 +176,7 @@ if ($success) {
        </td>
     </tr>
     <tr><td>
-        <input type="submit" name="cancel" value="<?php print_string('return', 'group'); ?>" />    
+        <input type="submit" name="cancel" value="<?php print_string('backtogroups', 'group'); ?>" />    
     </td></tr>
     </table>
     </div>

lang/en_utf8/group.php

@@ -84,6 +84,7 @@ $string['showusersalreadyingroup'] = 'Show users already in a group in the group
 $string['save'] = 'Save';
 $string['cancel'] = 'Cancel';
 $string['return'] = 'Return';
+$string['backtogroups'] = 'Back to groups';
 
 $string['groupfor'] = "for group";
 $string['groupinfo'] = 'Info about selected group';