nsPropertyMapper revision 3

[Neville Smythe]

I have uploaded version 3 of my drag-and-drop property management tool, which now handles patterns, graphic objects and images. Included is an ImagePicker which gives access to images in all open stacks as well as LC built-in images, allowing easier transfer of images between stacks, and many more icons than the LC Image Chooser; you can save favorite images, view image metadata, facilitate scaling an image to fit given bounds, and check your stacks for duplicate image IDs and unloaded images referenced in icons and patterns which could go missing in a standalone.