pokemon.update() used to be called after pretty much everything, but
now that we've refactored pretty much everything out of it, it's no
longer necessary for most of the situations we call it for.
It currently only updates pokemon.speed, so I've renamed it updateSpeed
for clarity.
We now only update pokemon.speed on switch-in, right before the
residual event, and at the beginning of every turn. This gives
something like a 30% speed-up.
The unwieldy system that is typesData is now removed, and is replaced by
the array `types` and the string `addedType`, which track the same amount
of information in a much more efficient way. (Roost is now hardcoded, but
let's not talk about that.)
Incidentally, this now roughly matches client, which tracks typechange
and typeadd as volatiles.
This allows us to remove ModifyPokemon, which overall provides a 10%
performance increase. I was hoping it'd be more substantial, but oh well.
