webify.real: convert Postscript to web-browsable html/gif subtree
		   - Steve Ward 3/16/95 ward@mit.edu
USAGE:
  webify <options> template psfile
    template is a text file containing prototype HTML and
      escapes which specify the configuration of generated
      GIFs and HTML documents (brief summary below).
    psfile.ps is the postscript file whose pages are to
      become web-browsable.
 <options> may include:
    -h    Horizontal (Landscape) mode.  The default.
    -v    Vertical (Portrait) mode.
    -f    Flip pages upside down (eg, like HP printers)
    -t "title" A title for the presentation.
    -T #  Thumbnail resolution (hence size). Default is 10.
    -S #  Slide/Page resolution (hence size).  Default is 50.
    -g <name> Use <name> as command to invoke Ghostscript.  Default 'gs'.
    -d    Debug mode.

Escapes in template include:
    {title} - insert title.
    {quietly ...} - evaluate for escapes, no output.
    {crop-top #} Crop # (a float) from top edge.  Similarly for
        crop-bot, crop-left, crop-right.
    {slide-resolution #} set slide resolution/size (default 50)
    {thumbnail-resolution #} set thumbnail resolution/size (default 10)
    {vertical}, {horizontal} - like -h, -v command options.
    {FlipPage} - like -f command option.

    {for-each-page ...} - repeat ... for each page. May include:
      {thumbnail} - reference to thumbnail GIF for current page.
      {slide} - reference to slide GIF for current page.
      {this-page}, {next-page}, {prev-page}, {first-page}, {last-page}
          - references to per-page HTML files.
      {write-page-file ...} Put ... in current per-page HTML file.
      {write-file fn ...} Put ... in file fn.
      {page-number [fmt]} - numeric page number, formatted per
          printf format [fmt].  Default is "%d"
      {pages [fmt]} - total number of pages, formatted per [fmt].

NB: Webify invokes Ghostscript (via gs command).
    Gs 2.6.1 must be installed and have gif8 conversion enabled.