Fixed bug where teachers could not properly see groups submissions.

forms/submissionview.php

@@ -99,7 +99,7 @@ if (! $subinstance) {
 }
 $submissionid = $subinstance->id;
 
-if ($vpl->is_inconsistent_user( $subinstance->userid, $userid )) {
+if ($vpl->is_inconsistent_user( $subinstance->userid, $userid ) && !$vpl->has_capability( VPL_GRADE_CAPABILITY )) {
     print_error( 'vpl submission user inconsistence' );
 }
 if ($vpl->get_instance()->id != $subinstance->vpl) {