* src/descriptor.h, src/descriptor.c: added a p_decoded field to the
    dvbpsi_descriptor_s structure and added an 's' to the
    dvbpsi_DeleteDescriptors function.
  * src/tables/pmt.c: added 's' where needed.
  * src/tables/pat.h: typo in the documentation.
  * src/descriptors/dr_02.h, src/descriptors/dr_02.c: MPEG2 "video
    stream" descriptor decoder and generator (not tested).