Add Drag'n'drop to run games from local files

[justgook]

Part 1:
Add ability to drag Tiled.json (maybe XML?), or multiple (images, tilesets) on main game engine webpage (should be divided by game templates - Platformer, shmup, figthing game... ), and as result get game running

Part 2:
after game running - add button to save it to firebase (or other storage) to be able share link.

[justgook]

Done in develop