This updates `fmt` to the latest version and moves to just being a copy
of their repo to make updating easier (no editing their cmake / figuring
out which files to minimally include).
The motivation for this is now that we switched to C++ 20, there were a
ton of deprecated function usages that is going away in future compiler
versions. This gets rid of all those warnings.
Supports most of the grain types now while maintaining compatibility
with the old stuff (at least the subset of things jak1 uses)
Would benefit from some testing in Jak 1 to make sure I didn't break
anything.
Sorry the git history is a mess, I'll do something about it later.
Tyler Wilding