Cutting release 4.18.1

[Matteo Merli]

Hi,

there have been quite a few bug and security fixes in the 4.18 branch,
and I think it's a good time to make a patch release.

If there are no objections, I'll start soon with a release candidate.

Thanks,
Matteo


--
Matteo Merli
<mme...@apache.org>