The way how it looks? Sure, that should be possible. You could allow the user to input a location of an image file (such as the image with tiles Tiled uses) somewhere and then have the game load the image from the link.
Another way would probably be to store the image as a text string (the name base64 comes to mind, perhaps something like that has been mentioned on the forums somewhere, a plugin, perhaps), then just have the user paste it.
As for the arrangement of things, you could probably store information in a .csv file and use something like csv2array.
-Sent from my outdated android phone.