Initial commit. Server and client.
Moves Microevent out to its own file.
Moves client libs to client/.
First working cross-network Twine link.

Several issues:
- When clicking links through jQuery, Twine behavior fires before Unity
  new room behavior, so story progresses before Unity calls back to JS.
- Mobile doesn't render the web player, so the Twine/Unity ping-pong
  of callbacks doesn't properly advance the mobile client.
- Unity web player stops itself when the browser loses focus, making
  it hard to test with multiple windows.
- Needs a lot of support in the Twine target header.html; needs to
  include tg_client.js, twine_bindings.js, and microevent.js.
Adds Twine gamepad support files.
Adds passage arrival events to sync clients.
Restores proper room name generation.
Improves README.