Adds a name attribute to GameObjects, which is to be used instead of isinstance() in collision handling
Adds a general class for powerups, that all powerups and debuffs can
inherit from.
This class takes care of drawing and most of the initializing, but does
not handle collisions.
The beginning of a Spikes class.

Works: Drawing spikes that are not flipped, colliding with them
Maybe works: Upside down spikes
Doesn't work: Death by spikes.