Non static state

[luleyleo]

Still needs some polishing, but it's mostly done.

[Saethox]

I had some trouble building this under Windows (my fault for using it :D), which was mostly because of coco-sys.

Some notes:

• The python executable under Windows is usually called python (not python3). Maybe use something like this in the build script?

#[cfg(target_os = "linux")]
let python_path = "python3";
#[cfg(target_os = "windows")]
let python_path = "python";

Command::new(python_path)
    .arg(build_script_path)
    .arg("prepare-build-rust")
    .output()
    .expect("failed to run prepare-build-rust command");

• libclang can be installed under Windows using the choco llvm package (Maybe add this to the README of coco-rs?)

  choco install llvm

With those, it compiles properly.

[luleyleo]

Everything should be working now.

[Saethox]

LGTM, I think we can merge.