(cherry picked from commit 0748bd98)

(cherry picked from commit 99f83484)

The release candidate -rc1 has version "1.y.90", -rc2 has "1.y.91", and so
on. Fix the script.

(cherry picked from commit 7f93fd8e)

The release candidate -rc1 has version "1.y.90", -rc2 has "1.y.91", and so
on. Fix the script.

(cherry picked from commit 8e9e6fd0)

Still not implemented are the first release candidate (rc1)
and the major release.

Currently only "minor" and "devel" releases are implement. It's also not yet
tested with --no-dry-run, because that would actually create a release.

Test it when using it the next time.