Largely to enable dependency injection.
I am pushing AWAY the paranoia that metatable lookups will slow things down. (You've got like 20 entities, bud, chill.)
Field -> Fielding
* Look at limiting batting/throw power with math.log()
* Extract draw/fielder.lua
* Extract some values into constants.lua
* Extract npc.lua for computer batting (and eventually probably more CPU behavior)
* pitchTracker in utils