Relay prototype

Considering getting this simple relay implementation into ThaliProject while I finish up the other aspects of it - to simplify folks using the HTML5 seed.   Perhaps into a new branch on ThaliProject - but then you wouldn't be able to see the diff for review.

Only one source file here for the relay - RelayWebServer.java (and RelayWebServerTest.java).  The other bits are all NanoHTTPD.  Open questions on code file headers for those....
I don't understand. Why would our decision to use chunk transfer on our response have anything to do with the fact that we received a response using chunked transfer? Shouldn't we *always* use chunked transfer on our responses regardless of the use of chunked transfer on the incoming request?