lots of minor fixes:

- get rid of the useless form
- fix css to reflect html changes
- instead of wrapping everything in $(function() {}), define functions in separate files for easier readability because the code was getting terribly messy
- move appendLog to MoeChat.appendLog and all the image upload code to MoeChat.initImgUploads
- move msgbox keydown binding inside conn.onopen along with the send button onclick
- rename MoeChat.server to MoeChat.otr because server was a terribly unclear name
- add actual error handling for image uploads