* Update helpcontent2 from branch 'master'
  - http -> https
    
    Turns out the https://www.oasis-open.org/standards#opendocumentv1.2
    page has linked them badly with http ...
    
    Change-Id: I64d26f79f4503a6b795c4990cf92327d20fbb08a
    Reviewed-on: https://gerrit.libreoffice.org/65459Reviewed-by: Eike Rathke <erack@redhat.com>
    Tested-by: Jenkins