Also add variation in spawn point, so that all spawns are not on top of
each other

At this point I've pretty much deleted all of Calinou's code. Oh well,
it DID get me started.

In multiplayer, if there is only one hero 1, it is ok, but with more
than one, one hero 1 cannot place walls.

Changing the weight of the objective fixes the weird destroy-the-player
physics.

Also, count how long the objective has been tilted to the right or left,
and put counters there. Slow the game down and display who won when the
count exceeds 100% on either side. Like in overwatch, but with tilting.

This reverts commit 22cf954991.

While on wall, if you press jump, you leap up and away from the wall

If you do so immediately after leaving the wall (<tolerance=.150s), it
still works

Unfortunately, apply_impulse seems to have no effect right now. More
research is needed.

There however were some bugs that came with this, so I'm switching to
master to explore this.