Linux support?

[JensForstmann]

Since I used this on my windows machine a while ago I just thought I would use it on my new linux server as well... Turns out despite being written in python it is not ready for linux usage out of the box.

I hacked something together (changed a few things) to get it working in my setup. It was mainly to change the path/binary to steamcmd and where the downloads are stored.

Is there any plan to update it for proper linux support? If so I could prepare a PR but I'm not sure because it would propably break some stuff for windows so there must be put in a bit of effort to get it right for both parties.