I noticed that jak 3's compilation was spending a lot of time accessing
the `unordered_map`s we use to store constants and symbol types.
I repurposed the `EnvironmentMap` originally made for GOOS for this. It
turns out that we were copying the entire constant map whenever we
encountered a `deftype`, and fixed that too.
This speeds up jak3 compiles from ~16 to 11 seconds for me.
water111
cc8801a27b