Statically link release binaries

[terror]

This PR uncurses #269, we believe that there is something wrong with the cache.

[casey]

We gave up on on statically linking arm builds. x86 Ubuntu doesn't include an ARM + musl linker, so we would have had to use cargo cross or install the toolchain ourselves. cargo cross gave us weird errors, so we gave up on that. We could install a arm musl cross compilation toolchain (which would include a linker) ourselves, probably from https://musl.cc. But, we figured that we would much of the benefit of static linking just from doing it on Mac, Linux, and Windows, so that's what this PR does.

[casey]

Pushed a tag.

[casey]

Pushed another tag, which built, so LGTM.

@soenkehahn I'm inclined to merge this. It statically links more binaries, and arm is tricky, so not doing it for now seems like a good idea.