Custom auth should be documented a little more

[jazeee]

EDIT:
I was wrong about the original ticket.

** Deleted original request. **

I believe the documentation should describe the function signature, and what it expects as a response such as:

Restivus.configure 
  auth: 
    user:  ->
      token = @.request.headers["x-auth-token"]
      ... Do something with token and extract your user...
      if notAllowed(user) throw new Meteor.Error("Unauthorized")
      return user

[jazeee]

Sorry, I misunderstood how the Complete Auth works. I do believe a little more documentation will help with understanding.

[kahmali]

I agree that the auth section of the docs needs some improvement. I made a small update for #91, but the custom auth needs to be explained there as well. I'll keep this open until it's updated.