Add/Support unknown or unlogged users

[strategio]

To give ability for unlogged users to leave comments, the name label should be editable (input field) if the user is unknown.

[aroc]

The way I was planning to handle this was just like Medium where you have to log in to leave a comment, but the button "Add a comment" still shows and emits events when clicked. What might work here is that when a user clicks the "Add a Comment" button and they are not logged in (which means SideComments doesn't have a currentUser set), you can bind to the event that gets emitted (addCommentAttempted) and show a form of some kind allowing someone to put in their information. Then you can setCurrentUser(userFromForm) and allow them to post a comment.