Add Support for Key Combinations

[xliiv]

Is it possible to register a key combination? For example

fn main() -> Result<(), Box<dyn std::error::Error>> {
    use livesplit_hotkey::{Hook, KeyCode};
    let hook = Hook::new().unwrap();
    hook.register(KeyCode::Alt + KeyCode::Space, || println!("combo!")).unwrap();
}

I didn't find anything I assume it's not possible, but i also could overlooked it.

[CryZe]

Yeah you can't do that yet. Let's use this as a tracking issue for supporting this eventually.