Add extra chat room commands: /nick, /mute and /voice.

Also document the available chat room commands.
Provide feedback if a chat room command didn't work.
Bugfix. Chat room status messages weren't being shown in certain cases.
Refactor showing of chat room status messages.

onChatRoomPresence and showStatusMessages have been refactored to give more
detailed information and to also show the reasons given to actions taken by
moderators.
Test that user is properly informed when kicked out of a room
Tell travis to run 'make dev' first
Use strophe from bower packages
Define jed path in main.js, not locales.js
Sort dependencies by name
Move all path declarations from locales.js to main.js

Makes it easier to integrate converse.js into other bower/require projects.
Update translation docs to mention paths in main.js
Also declare the template paths in main.js
Make sure main.js is loaded before calling require.

When calling require from within HTML, then don't use data-main, but instead
load main.js via a require call.

See here: http://requirejs.org/docs/api.html#data-main
Provide single-session support.
Add docs on keepalive setting.
Only save the session if it's valid.
Avoid double scroll-bars in control box
Add the ability to log out of a session. updates #80
Refactor chat rooms.

When re-attaching to an existing session, chat rooms are fetched from
sessionStorage and we join them again.

However, unless we send a presence of type unavailable before reloading the
page, from the XMPP server's perspective we never left the chat room.

It therefore doesn't send us again the room occupants or room messages.

To send a presence of type unavailable is a hack and not desireable. Rather, we
want to stay in the room and just re-attach to it upon page reload.
In order to do this, we need some new functionality.

* Refactor the chat room sidebar into a new Backbone Model/View combo. (done).
* Store/fetch room occupants in/from sessionStorage (done).
* Store/fetch room messages in/from sessionStorage (not yet done).
* Instead of re-joining a chat room which we never left, just register the event handlers again. (not yet done).
Give chatroom's occupants view a ref to the chatroom view

and thereby fix bug with directInvites.