Fix radius sizes argument in mean image filter constructor in field module header.  https://tracker.physiomeproject.org/show_bug.cgi?id=3759
Fix radius sizes argument in mean image filter constructor in field module header.  https://tracker.physiomeproject.org/show_bug.cgi?id=3759

hsorby/zinc,hsorby/zinc,OpenCMISS/zinc,hsorby/zinc,OpenCMISS/zinc,hsorby/zinc,OpenCMISS/zinc,OpenCMISS/zinc