Proxy_write_path is ignored

No matter what I set as proxy_write_path, that path is ignored and the default path /temp/proxy is used.

I found that the proxyWritter function (proxy_writter.js) doesn't take the path as an argument.

I fixed this on my side by adding proxy_write_path as an argument and taking it into account in that function.

I can create a pull request if you like.
