Missing mac build

[alexchandel]

Could you provide a macOS .whl? The macOS build environment is similar to linux (except usually clang/LLVM instead of gcc), and much simpler than Windows. You can assume build tools are already in the PATH (they can be installed on vanilla macOS by xcode-select --install).

[ksmyth]

I don't currently have the time to work on this. I'd accept a PR that uses appveyor or travis.