Some kind of deathmatch implementation

[spazzylemons]

I don't remember if/what we decided on how to do this but the general idea is when there is only so much time left, shrink the border down around spawn and teleport players back to their spawn points, so that players cannot stay outside of the border to avoid being hit, to make players more visible in general, and to encourage a game to end quickly. Discussion of the specifics of the implementation would be good.

[spazzylemons]

Another idea discussed during playtesting: Manually impose damage for being outside of world border