Add 2006/stewart/try.sh

It will run the program on a few files but before it runs it on the
remaining files (as there are quite a lot) it will ask you if you wish
to do so. It only asks once. If convert is found it will run convert on
the xbm images to convert to png. If it's not installed it will only
warn the user once so as to not spam them. If convert fails (say because
the convert is not convert from ImageMagick) it will warn once at the
end of the script. In any event if any files were converted it will list
the png files that exist at the end of the script. Otherwise it'll list
the xbm files. It does not first check if any of those file types exist
as it is presumed that at least a few will exist. If none do it is
likely an error in the program or a corrupted data file.

2006/stewart/README.md

@@ -30,17 +30,18 @@ NOTE: `convert(1)` belongs to [ImageMagick](https://imagemagick.org/index.php).
 ## Try:
 
 ```sh
-./stewart 400 1000000 maze > maze.xbm
-convert maze.xbm maze.png
-
-./stewart 1024 1000000 gasket > gasket.xbm
-convert gasket.xbm gasket.png
-
-./stewart 1024 1500000 dragon3 > dragon3.xbm
-convert dragon3.xbm dragon3.png
+./try.sh
 ```
 
-Now open the images in your favourite graphics viewer or a web browser.
+After running the program on a few files it will ask you if you wish to run it
+on the remaining files.
+
+The script will try converting the xbm files created by the program to png
+files. If it does it will list those that exist in the directory, at the end of
+the script. If you do not have `convert(1)` it will warn you once. In that case
+you'll have to open the xbm files in a graphics viewer capable of viewing xbm
+images. In any case choose your favourite graphics viewer to look at the images
+created.
 
 
 ## Judges' remarks: