[build2] Thanks for working on build2!

[duarm0]

Hello, thanks for working on build2!

I've tried to use build2 many times before, but was never able to convert my project 
to it, I have a bunch of dependencies from both my system and prebuilt static libs.
Today I partially moved to build2, one thing I've always wanted to do was to static link
my program, and that was very easy to do with build2, I was so happy when I ran 
`b configure config.bin.exe.lib=static` and libz was automatically built as a static 
library and linked with my program, when I added -static and it magically static 
linked-libc, how? My system's default libc is glibc, and I thought it wasn't possible to
static link glibc. Maybe there's an easy way to specify musl instead? Anyway, just wanted
to encourage the devs.

Regards,
duarm.