add GroupTileLayer internal sort of sublayers (#1680)
add GroupTileLayer internal sort of sublayers (#1680)

* fix ios 13 MediaQueryList not addEventListener

* add GroupTileLayer internal sort of sublayers

Co-authored-by: 潘振东 <ed1cb22110fd1aba3bcac288603c4939ef11f471@yuan9.cn>
MapTalks/MapTalks.js