Add help document interface.
Use json document to print json help.
Define stub plain help document.
Update help write logic.
Update help document interface.
Fix help section constants.
Work on re-instating section headers.
Prevent duplicate command sections.
Tidy obsolete functions.
Assert on help event.
Assert on help document code paths.
Assert on gnu document code paths.
Complete help class assertions.

100% code coverage.
Assert on writing help to streams.

100% code coverage.
Assert on setting help style.
Assert on synopsis help style.
Assert on custom help section.
Pass stream to help listener.
Work on gnu help compatibility.
Work on the help output alignment logic.