+windows support

Hi, again!
I've changed a few files to make goji compilable and usable on windows by basically stubbing out parts that are einhorn/systemd-related - as I'd really like to use the original repository! I'm developing on windows (where it is a problem) and deploy to heroku (where it isn't) - my first stab was to fork, but with a fork I had to change the package paths which is not ideal.

Thanks!
dmitri.