v0.13.1

Added

• ALWAYS_AVAILABLE_VIEWERS in @collabdt/core/core/utils/appContent: the map, plugins and settings viewers,
  which every organization has whatever its appContent lists.

Changed

• resolveAppContent always includes the map, plugins and settings viewers, not only the map.
• The organization setup form no longer shows a locked Map checkbox, so map is no longer submitted in
  appContent.

Removed

• The OrganizationConfig.viewerMap message, which only labelled that checkbox.

Fixed

• The Plugins page and Settings open for every organization. isViewerAllowed refused any viewer missing
  from a non-empty appContent. Organizations whose list predates plugins or settings saw the sidebar entry,
  but clicking it left them on the map, sometimes with the ?viewer= parameter flipping back and forth.