Initial implementation of chat

I have made an initial implementation of the chat boxes.  Users are randomly assigned a username when accessing the site until we have some sort of login system in place.  They may choose to change the given user name with a special chat command.

There are currently 2 sections to the chat pane.  The top section is capable of having multiple tabbed chat rooms attached to it.  By default only global chat is loaded.  The bottom section is intended to be only for local chat (street level chat).  It cannot be changed or added to by the user.

Still to be done:
-Although the top pane supports more than one tab, if you have more than three they wrap to the next line and half-cover each other.  This could be solved perhaps with a scrolling system or some other organization system.
-The chat server is hosted as a dart app running on Heroku under my account.  Perhaps this should be hosted under some common account?
-I do not have write access to the coUserver repo so the chat server file is only on my machine at the moment.