So take every possible supported combination of endian, fpu/no-fpu, target arch
(and random sub variations thanks to the ability to have custom cores on MIPS
and ARM and the like), and on and on and on..

It becomes pretty nice to be able to `nim build -d:target=<target>` and go have
various `target/<target>.nims` files pull in the various configs they need...

Otherwise I have to write a massive parser for all possible targets to find a
config entrypoint.. which is kinda lame