Implemented PassthroughLoggingHttpProxy.

Added PassthroughLoggingHttpProxy and PassthroughForwardHttpRequestBuilder to help out in setting up a domain and port passthrough to the external service.

Example usage:

> new PassthroughLoggingHttpProxy(PORT, "www.google.be", 80 , loggerFactory);

This will redirect all request on localhost:PORT to google.be:80 and log the conversation.