work on adding comments to restaurant show page

Created CommentsController
change restaurant controller (prob was a no no)
Did some other things that simply did not work.  I'm tired. should rest and tackle this in the morning. 
Any good feedback would be welcome. 
Do you have a `build_comment` method defined on `Restaurant`?

You could probably do something like this here instead:

```
@comment = Comment.new(comment_params)
@restaurant.comments << @comment
```