Guile-SDL demo-1 and demo-2 updated

[Thien-Thi Nguyen]

folks,

the two slow-to-evolve-but-fun-to-play-w/-nonetheless Guile-SDL demo
programs are available in dir:

  http://www.glug.org/people/ttn/software/guile-sdl/

among other changes, they now make use of the module (sdl simple),
introduced in Guile-SDL 0.3.1.  below is output from invoking each
program w/ option "--help".

thi

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$ demo-1 --help
Usage: view-vcg [--geometry WxH] [--quiet] [--batch] VCG-FILE

You can use -g for --geometry,
            -q for --quiet,
            -b for --batch.

When `--batch' is omitted, `--geometry' MUST be specified.  Keybindings:
`e' toggles edge visibility; `s' increases vertex size; and `a' and `d'
rotate counter- and clockwise, respectively; ESC quits.


$ demo-2 --help
usage: demo-2 [ --help | --version ]
       demo-2
       demo-2 --site
       demo-2 FILE ...

Show results of frisking FILE ... in a window.  Internal modules form the
inner "sphere", and external the outer.  Arrow keys in conjunction w/
right-shift change the rotational velocity for different axes.  SPACE
pauses.  RET kills all velocities.  `n' chooses a new random arrangement.
`a' toggles "auto-tweak mode".  `l' toggles module labels.  `r' cycles
through four "refresh modes".  `d' toggles "diamond halo".  ESC quits.