now be specified as --srcdir=top_srcdir (or --source-directory=top_srcdir
or -S top_srcdir). Changed po/Makefile to match.
This option can even be repeated; that resolves a BUGS item.
Changed po/Makefile to ignore exit codes from check-accelerator-contexts.pl.
Enabled bundling of options in Getopt::Long so that -Stop_srcdir works too.
The detailed documentation is now as POD in the scripts, and the README
just gives an overview and describes how the scripts relate to ELinks.
The intention here is to make the scripts more readily usable for programs
other than ELinks. The scripts now describe their licensing, too.