Default line break handling is inconvenient

Spec
53

For example, this interaction designer

http://talk.commonmark.org/t/lists-without-a-list-indicator-character/861

A solution would be to make line break handling default, selectable by admin. And also to be able to override line break handling via document declaration. Here is a mockup of first few line of document declaration, with a “Line_Break” field:

!CommonMark: 0.1.23-github.username.projectname
 Title:      Title for the top bar of any browser
 Date:       32-4-2002
 Line_Break: On