Introduced a --ts-extra-pmt <pmt_pid=pid:stream_type[,...]> option to
 allow user to enter a pmt description (for stream without PAT/PMT).

    TODO: - test all codec.
          - test stream with more than 1 PMT
          - test stream with PAT/PMT change(s)
          - re-add support for dvb subtitles.
          - test with broken streams.
          - test --ts-extra-pmt