documentation docs gplv3 public-domain rdoc gpl3 rdoc-lang rdoc-language pdnet pdnet-plus-plus public-domain-streaming-network public-domain-streaming-network-plus public-domain-streaming-network-plus-plus pdnet-plus-plus-channels pdnet-plus-plus-docs pdnet-plus-plus-documentation pdnet-plus-plus-project pdnet-plus-plus-development public-domain-streaming pdnet-plus-plus-channel-pbs