Prevent startup on Windows

There's way too many things to fix before this has any chance of working.

websockify/websockifyserver.py

@@ -37,6 +37,9 @@ for mod, msg in [('ssl', 'TLS/SSL/wss is disabled'),
 if sys.platform == 'win32':
     # make sockets pickle-able/inheritable
     import multiprocessing.reduction
+    # the multiprocesssing module behaves much differently on Windows,
+    # and we have yet to fix all the bugs
+    sys.exit("Windows is not supported at this time")
 
 from websockify.websocket import WebSocket, WebSocketWantReadError, WebSocketWantWriteError
 from websockify.websocketserver import WebSocketRequestHandler