LabelMultisetType.copy passes img and access as reference to a new LabelMultisetType. Other NativeTypes, e.g. UnsignedLongType.copy, create a new single value object without any backing img or access. LabelMultisetType should follow this scheme. At least, it should update the index i of the newly created type.
LabelMultisetType.copypassesimgandaccessas reference to a newLabelMultisetType. OtherNativeTypes, e.g.UnsignedLongType.copy, create a new single value object without any backingimgoraccess.LabelMultisetTypeshould follow this scheme. At least, it should update the indexiof the newly created type.