The patch adds two new levels to the backup form structure: subsection
(a delegated section which parent is a course module) and subactivity
(an activity inside a subsection). Those new elements are displayed as a
inner section below the parent activitiy.
For now the UI is the same as a regular section but future issues will
define how the UX should be. The new two levels have their own classes
to represents settings and have extra dependencies.
Andrew Nicols