WIP: First pass at notification messages for adding/moving users.

@andy-armstrong This is what I got done today on notifications. I think everything is working (except the bug I commented on in the code), but I didn't get to tests at all. Also the UX doesn't exactly match the mockups (bullets are showing for li items).

I decided not to add more small JS files and instead piggy-backed on existing files. I also noticed that you hadn't been declaring all the dependencies (like JQuery and Underscore).