Support custom images for objects? #3504

Is your feature request related to a problem? Please describe. My game uses a custom property on objects to define a sprite for that object in-game.

Describe the solution you'd like I'd really like to be able to extend tiled in some way so that the objects show up with the correct sprite in the editor.

Describe alternatives you've considered I'm not aware of any alternative solutions to try, but I'm happy to try them out if there are any. I'm also happy to help contribute to this change if needed with some guidance.

Thanks for the great software! ❤️