Accessing livereload via proxy

This commit adds a couple options to make it easier to access the livereload server via a proxy. I'm doing development work on a separate virtual machine from where my actual dev environment lives, in order to test out HTTPS features. However, that prevents the livereload script from working properly, since the browser refuses to run a script from an insecure channel on a secure page.

The two options added by this patch let me use my HTTPS proxy to access the livereload server.