* lisp/subr.el (purecopy-cons, purecopy-car): Add shortcuts.

* lisp/subr.el (purecopy-cons, purecopy-car): Add shortcuts.
* lisp/faces.el (face-x-resources): Use `purecopy-cons'.
* lisp/files.el (auto-mode-alist, interpreter-mode-alist): Use
`purecopy-car'.
* lisp/international/fontset.el (font-encoding-alist): Ditto.
* lisp/international/mule-conf.el (file-coding-system-alist): Ditto.
* lisp/international/mule.el (auto-coding-alist)
(auto-coding-regexp-alist): Ditto.
* lisp/mouse.el (mouse-buffer-menu-mode-groups): Use `purecopy-cons'.
* lisp/term/x-win.el (x-gtk-stock-map): Ditto.