design login panel

Just design--no js yet.
Add beginnings of transition to chat from login

Request login from server, if success clear the body and load chatPage.js.

Add a new signal "readyForData" which the client sends when it is ready to
 start receiving messages. This signal does part of what the login response
 used to do: supply the client with the messages and users logged in.
Upon login, load empty chat page with no funcitonality

This introduces chatPage.html and it's corresponding css. chatPage.html is
inserted into the body of the index page by chatPage.js after the user
authenticates.
Support sending and receiving messages
Add login notifications

This involves updating the user panel and displaying notifications when users
log in and log out.
Stick the messages scroll bar to the bottom on new messages

If the scroll bar as at the bottom already, keep it there as new messages are
added. Otherwise don't anchor the scroll bar to the bottom.
Remove unneeded files.

This feature changed almost everything in the client side, here are all the
old pages that are now gone!
Merge branch 'refactor-view'