User option for multibyte buffer handling and doc fix.

User option for multibyte buffer handling and doc fix.
(ps-multibyte-buffer): New user option.
(ps-setup): Print new user option.
(ps-print-quote): New fun.
(ps-color-p, ps-mule-font-info-database-latin): New var.
(ps-default-color, ps-mule-font-info-database)
(ps-mule-font-info-database-ps-bdf): Adjust initialization.
(ps-mule-get-font-spec, ps-mule-begin, ps-begin-file)
(ps-plot-with-face, ps-generate-postscript-with-faces, ps-generate):
Little code improvement.
(ps-mule-initialize): Initialize ps-mule-font-info-database.
(ps-print-prologue-header, ps-font-family, ps-font-size)
(ps-header-font-family, ps-header-font-size, ps-header-title-font-size)
(ps-build-face-reference, ps-mule-font-info-database-bdf)
(ps-mule-external-libraries, ps-mule-init-external-library)
(ps-mule-prepare-font, ps-mule-find-wrappoint, ps-mule-plot-string): doc
fix.

To make it work also on Emacs 20.2 and the earlier
version, check the value of mule-version.

(ps-print-version): New version number (4.1.1) and doc
fix.
(ps-print-prologue-header): New user option.
(ps-color-values, ps-xemacs-face-kind-p, ps-mapper, ps-extent-sorter):
Conditional compilation for GNU Emacs and emacsens.
(ps-generate-postscript-with-faces): Skip invisible text better.
(ps-setup): Print new user option.
(ps-print-preprint): Check if input file name exists and is unwritable.
(ps-begin-file): Adjust PostScript prologue header for duplex printers
and insert user PostScript prologue header comments.
(ps-mule-encode-bit, ps-mule-string-ascii, ps-mule-string-encoding): New
funs.
(dos-ps-printer, lazy-lock-fontify-buffer): Eliminated.
(ps-mule-prologue, ps-mule-cmpchar-prologue, ps-mule-bitmap-prologue):
PostScript programming normalization.
(ps-mule-encode-7bit, ps-mule-encode-8bit, ps-mule-generate-font)
(ps-mule-generate-glyphs, ps-mule-prepare-font, ps-mule-plot-string)
(ps-mule-skip-same-charset, ps-mule-plot-rule-cmpchar)
(ps-mule-plot-cmpchar, ps-mule-prepare-cmpchar-font)
(ps-mule-initialize, ps-mule-begin, ps-face-bold-p, ps-do-despool):
Programming style normalization.