Another small change. I added a simple version of the "bump" you get
when you jump on another player. Was playing the real version for
comparison and noticed something. When you jump on a player, the screen
shakes a little up/down to signify a stomp. I implemented something that
looked close.... but took out the actual call to it. You have to make
the gameframe available to the player and have the "bump" method called
from player when a player gets crushed.