A proxy aware dialer. See https://github.com/cloudfoundry/cli/issues/127 for more info.

By default, if no proxy URL function is set when creating the consumer, the 'http.ProxyFromEnvironment' will by used. The proxy URL function is responsible to provide the URL of the proxy server to be used.

The URL resolved will be used to establish a TCP connection to the proxy server following with a HTTP CONNECT request in order to establish a proxied connection to the loggregator server.

If no proxy URL is resolved or the loggregator's URL should not be proxied, dialer will fall back to 'net.Dial'.