Working on Windows + minor change

Hey @felixge, 

Great work with this. I'm sending this PR because when I tried your package on Windows it blowed up. Basically `getuid` and `getgit` aren't supported on `process` for Windows.

Also, I've change the `params` parameter to be `req.body` as req.params returns what's on the URL.

Disregard my changes on the `package.json`