Additional issue fixes

mod/cal.php

@@ -96,8 +96,6 @@ function cal_content(App $a)
 		'$baseurl' => System::baseUrl(),
 	));
 
-	$o = "";
-
 	$mode = 'view';
 	$y = 0;
 	$m = 0;

mod/contactgroup.php

@@ -40,7 +40,7 @@ function contactgroup_content(App $a)
 			}
 		}
 
-		if ($change) {
+		if (x($change)) {
 			if (in_array($change, $preselected)) {
 				Group::removeMember($group['id'], $change);
 			} else {