Server-side support for teleport pads: 5 points

[nataliavelez]

As an experimenter, I can hard-code the location of teleport pads that enable players to transmit objects across walls.

For example, this map configuration

[[p1c1, 0, 1, t3, w, t3, 0, 0, 0, 0],
[0, 0, 1, 1, 0, w, 0, 0, 0, 0],
[1, 0, 0, 1, 0, w, 0, 0, 0, 0],
[t1, 0, 0, t2, 0, w, 0, 0, 0, 0],
[w, w, w, w, w, w, w, w, w, w],
[t1, 0, 0, 0, 0, w, t2, 0, 0, 0],
[0, 0, 0, 0, 0, w, 0, 0, 0, 0],
[0, 0, 0, 0, 0, w, 0, 0, 0, 0],
[0, 0, 0, 0, 0, w, 0, 0, 0, 0],
[0, 0, 0, 0, 0, w, 0, 0, 0, 0]]

Should produce this map, which has teleport pads that transport objects in the directions indicated by the arrows:

[silviot]

I started implementing this, and I think most of the work related to this feature is about allowing two different objects to be shown in the same cell.
So teleport pads can't be objects on the grid. They need to be a property of the tile, similar to walls.