Post message without requiring page reload (fixes #2)
Switch back to SetTimeout, but make the timeout clear on function call; This allows updateChat to be called independently wihtout setting up multiple timeouts
Switch to using the form id instead of the button id; This allows one to hit enter to submit a chat message with AJAX as well
Return a success message from post and update the chat based on that success message
Merge pull request #5 from caxy/master

Don't require page reload to post message