Support for moving x/y for multi-region/multi-graphic subpicture.
Make scalefactor double.
Scale window position/size values for multi-region sups.
Scale position/size for multi-graphic XML.
Update constructor for new fields.
Use new SubPictureBD methods for accessing window sizes.
Use new methods to access image rects from SubPictureXML.
Support calls to scale windows for multi-region/multi-graphic subpictures.