Add TLS support and Facebook chat demo (only for firefox)

Add TLS support and a Facebook chat demo.  This only works for Firefox for now, and will break Chrome until chrome.sockets.tcp.setPaused is updated (https://code.google.com/p/chromium/issues/detail?id=403076).
worry is that this will break any delegated domains, e.g. cs.washington.edu has an xmpp srv record delegating to google. The DNS request is needed to learn about the delegation.