XEmacs compatibility. Doc fix. Can select page size

XEmacs compatibility.  Doc fix.  Can select page size
with/without giving an error if PostScript printer doesn't have this
kind of page size.  Zebra Stripe continues or restarts on next page.
Manual/automatic paper feeding.  Switch or not the header.
(ps-print-version): New version number (5.2.2).
(ps-windows-system): Include emx as a Windows system.
(ps-setup, ps-begin-file, ps-color-values, ps-screen-to-bit-face)
(ps-generate-postscript-with-faces, ps-generate-postscript-with-faces)
(ps-background-text): Code fix.
(ps-error-handler-message, ps-user-defined-prologue)
(ps-print-prologue-header, ps-printer-name)
(ps-print-control-characters, ps-n-up-filling, ps-zebra-color)
(ps-line-number-step, ps-spool-config, ps-default-fg, ps-default-bg)
(ps-use-face-background): Customization fix.
(ps-n-up-database): Data fix.
(ps-warn-paper-type, ps-zebra-stripe-follow, ps-manual-feed)
(ps-switch-header): New vars.
(ps-xemacs-color-name, ps-face-foreground-name)
(ps-face-background-name, ps-boolean-constant): New funs.