Add scoped and channel routes

- new section for scoped routes
- new section for channel routes
- some name changes based on what I see in the most recent versions of Phoenix.

//cc @chrismccord I know you have just completed a huge chunk of work getting the 0.4.0 release out the door (congratulations again on that!), but if you had a chance to look at this for errors on my part, I would greatly appreciate it! Thanks in advance.