JSON tilemap load ignores repeat-x/y #3424

Loading a tilemap in *.tmj ignores the repeat x/y settings for layers

To Reproduce Steps to reproduce the behavior:

1. Export a tilemap to *.tmj that has layers with repeat-x set for an image layer
2. Load the reulting *.tmj file in Tiled, and check if the repeat has been preserved
3. Look at the *.tmj file in a text editor to confirm that "repeatx":true, was included for that layer

Expected behavior The JSON tilemap should look identical to the original *.tmx. Everything appears to be loaded correctly, except for the "repeatx":true layer attribute (which is in the JSON file, I checked)

Specifications:

• Tiled Version: 1.9.0