[vcloud_director] Change input options structure.

  #put_guest_customization_section_vapp
  #put_network_connection_system_section_vapp

Although no longer documented, the previous options structure is still
accepted and is mutated into the new structure. This behaviour is likely
to be deprecated at some point.
Merge pull request #2280 from nosborn/vcloud_director_put_sections

[vcloud_director] Change input options structure.