Note that 'make web-manual' fails.
* NEWS: Document these changes.
* doc/Makefile.am: Adjust to generate example files.
* doc/bison.texi: Add a Graphviz section after "Understanding::", the section
describing the .output file, because these are similar.
* doc/figs/example-reduce.dot, doc/figs/example-reduce.txt,
doc/figs/example-shift.dot, doc/figs/example-shift.txt: New, minimal
examples to illustrate the documentation.
Signed-off-by: Akim Demaille <akim@lrde.epita.fr>
