fix documentation on cloning as anonymous user
fix documentation on cloning as anonymous user

raesjo/SKIRT,raesjo/SKIRT,raesjo/SKIRT,SKIRT/SKIRT,raesjo/SKIRTcorona,SKIRT/SKIRT,raesjo/SKIRTcorona,SKIRT/SKIRT,raesjo/SKIRTcorona