For the release candidates, allow passing the version (e.g. "3.1.1-rc")
to post-release.sh on the command line and document this.
Also don't commit automatically, this is annoying, especially as the
script doesn't check for errors.
Finally, fix the problem with the CHM file name: it must be zipped,
presumably to avoid problems with some firewalls blocking downloading
CHM files (as there is really no advantage in compressing the already
compressed CHM file otherwise).
35d2823601