Tagging v0.2.1

Changelog:
- Added better error handling.
- Added unique id to messages/events.
- Changed since parameter for channel.query (/recv) to use the unique id instead of the timestamp.
- Fixed demo so it doesn't auto-scroll if the user has scrolled up.
- Fixed demo to reset unread count on focus.

Tagging v0.2.0.

Changelog:
- Moved stdout logging from the channel to the demo (no built-in logging).
- Removed event prefixes in client, e.g., join instead of nodechat-join.
- Added events to the channel instances on the server to match the events on the client.
- Added error handling for invalid channels.
- Moved callback flushing and session expiration to each channel to reduce blocking.
- Updated to work with node 0.1.9x with no warnings.
- Simplified demo by serving all files in /web as static files instead of explicitly handling each file.
- Added error handling for dropped connections to the demo.
- Added success and error callbacks for nodeChat.join (client).
- Added a readme with documentation.

Tagging v0.1