Simplified the main event loop.
Simplified the main event loop.

This is the main source of memory usage, and the main bottleneck for
speed, so hopefully we should see a speed increase.

My tests show a speed increase of roughly 20%

noa/hearthbreaker,jirenz/CS229_Project,slaymaker1907/hearthbreaker,Ragowit/hearthbreaker,kingoflolz/hearthbreaker,slaymaker1907/hearthbreaker,danielyule/hearthbreaker