Log Message:
Changes 9.19:
* New custom PJL (near) equivalents for pdfmark and setdistillerparams.
* Metadata pdfmark is now implemented.
* An experimental, rudimentary raster trapping implementation implementation has \ 
been added to the Ghostscript graphics library.
* The halftone threshold array generation tools (part of toolbin/halftone) have \ 
been improved with thresh_remap which allows folding the transfer function (AKA \ 
toner response curve (TRC)) into the threshold array so that highlights are \ 
improved. Further, gen_stochastic has improved support for minimum dot size and \ 
shape.
* Plus the usual round of bug fixes, compatibility changes, and incremental \ 
improvements.