ProxyTunnel is a program that connects stdin and stdout to a server somewhere
on the network, through a standard HTTPS proxy. We mostly use it to tunnel SSH
sessions through HTTP(S) proxies, allowing us to do many things that wouldn't
be possible without ProxyTunnel.

Proxytunnel can currently do the following:
* Create tunnels using HTTP and HTTPS proxies (That understand the HTTP CONNECT
command).
* Work as a back-end driver for an OpenSSH client, and create SSH connections
through HTTP(S) proxies.
* Work as a stand-alone application, listening on a port for connections, and
then tunneling these connections to a specified destination.