Document --help-full in command-line usage output
Merge topic 'doc-full-help' into next

0051e8ba Document --help-full in command-line usage output
Restore --help-full option to output all help manuals

This option was removed during conversion to the reStructuredText
documentation.  Restore it.  Process documentation starting at
Help/index.rst so that all manuals are included in the output.
Merge topic 'doc-full-help' into next

478356e6 Restore --help-full option to output all help manuals