* doc/lispintro/emacs-lisp-intro.texi (Lists diagrammed)
(Symbols as Chest, kill-ring-yank-pointer, lambda): Use @image and
remove ASCII-art diagrams, which are now on separate *.txt files.
(header): Remove print-postscript-figures and its commentary.

* doc/lispintro/Makefile.in (auxfiles): New file list.
(${buildinfodir}/%.txt, ${buildinfodir}/%.png): New targets.
(${buildinfodir}/eintr.info): Depend on ${auxfiles}.
(infoclean): Remove ${auxfiles}.

* doc/lispintro/cons-1.png:
* doc/lispintro/cons-1.txt:
* doc/lispintro/cons-2.png:
* doc/lispintro/cons-2.txt:
* doc/lispintro/cons-2a.png:
* doc/lispintro/cons-2a.txt:
* doc/lispintro/cons-3.png:
* doc/lispintro/cons-3.txt:
* doc/lispintro/cons-4.png:
* doc/lispintro/cons-4.txt:
* doc/lispintro/cons-5.png:
* doc/lispintro/cons-5.txt:
* doc/lispintro/drawers.png:
* doc/lispintro/drawers.txt:
* doc/lispintro/lambda-1.png:
* doc/lispintro/lambda-1.txt:
* doc/lispintro/lambda-2.png:
* doc/lispintro/lambda-2.txt:
* doc/lispintro/lambda-3.png:
* doc/lispintro/lambda-3.txt: New files, from Matto Fransen
<matto@matto.nl>.