Add missing POD to SurveyJSON

Also fix a bug I noticed while updating POD - when removing a
multiple-choice bundle the question should have its questionType
set to the generic "Multiple Choice' question type rather than
leaving it set to the now-deleted bundle questionType.

lib/WebGUI/Asset/Wobject/Survey.pm

@@ -956,6 +956,7 @@ sub removeType{
     my $self = shift;
     my $address = shift;
     $self->surveyJSON->removeType($address);
+    $self->persistSurveyJSON();
     return $self->www_loadSurvey( { address => $address } );
     
 }