Update tex-prosper to 1.5 and remove dependencies on teTeX.

Based on patches from Nicolas Thauvin.

Changes:
* bookmarks for all overlays
* corrected bug preventing correct use of \cite in slides with overlays.
* corrected reinitialization problem of the current color when
  option "colorlinks" is true
* Now, counters are not incremented inside overlays. Added macros to support
  this. Labels should no longer reported multiply defined in overlays either.
* Prosper now supports Adobe distiller for transforming PS files into PDF
  files

(minskim)