* Support DVDs with errors on them. So we can recover from corrupt sectors in
  the .VOB. Be able to read the VAT ICB at the last sector of the UDF disk (see
  function UDFGetAVDP)
* Support Random and Shuffle Titles. Only sequential Titles are currently supported.
* rework documentation
* implement restriction levels:
   0 - execute everything as the app commands
   1 - do some sensible sanity checking
   2 - be more careful, when operations are prohibited (like not seeking/jumping in the presence of stills or cell commands)
   3 - fully respect user prohibitions
* cleanup public API and fix libtool versioning
* Update decoder.c with some of the more rare commands. Update already done to vmcmd.c