updated readme

did some more work on extensions, resulting in a rewrite of some inte…

…rnal componenets

- the message and response parsing were rewritten
- uses a single message object, with multiple interfaces
- added a send method to faye which wraps the call to the transport
- added a newMessage method to faye which returns a message object
- modified the response parsing in the public API
- most public API is the same

updated readme

used a mutex to ensure a single connection to the server per client

As per the bayeux protocol