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.
* merc dma generation
* wip very early version of merc
* small fixes
* fix
* fix more merc bugs
* derp fixed min
* oops we did need something weird on max
* merc for everything
* program optimization 1
* more optimization
* windows
* windows 2
* clean up
* fix test
* BLERC