Switch to pure meson build system and adapt configuration for SlapOS
requirements.

Support multiarch env by simply linking from lib64.

Version 249.6 incorporates fix from https://bugs.gentoo.org/824026 for:
  meson.build: ERROR: Object <[BooleanHolder] holds [bool]: False> of
  type bool does not support the +

This was removed from ERP5 in d9be34803b (erp5-util: remove zodbanalyze,
that is now a part of https://lab.nexedi.com/nexedi/zodbtools ., 2016-12-15)
but we were still installing a broken script here.

using ./format-json script

From now on, hosts keys will always be checked and there is no way
to disable the check

remove also software/unstable/zimbra-kvm which were still referencing
those recipes

using https://github.com/matomo-org/matomo/pull/13676

This repairs a NameError introduced in 397726e1 (erp5/neoppod/slapos:
Support for python3 from aurel/zope4 branch., 2022-02-03) that was
causing ERP5-IOS test suite to fail in loop.

a binary make use of it and do not any more download a binary. Instead
compile on the fly.

Nettle has hard dependency on openssl, and --disable-openssl is only
disabling optional feature of it.

This reverts commit 054386d6.

It proven to be insufficient to fix issues with PYTHON make variable
surcharging from top make.