Separate document comments from inline comments

Currently, all comments go into the same place. This can be difficult because while comments on the page may be commenting about the content as a whole (e.g. "Great blog, glad to see you're doing xyz!"), inline comments may be more specific. For example, they may highlight the word "linux" and then comment on that word ("Hey John, I'd love to understand why you went with Ubuntu here over CentOS. Was it performance?").

With the current implementation they get mashed together in one space, but there is great value in having them separated.