python or python2 is system python, which we want to avoid

Co-authored-by: Kazuhiko SHIOZAKI <kazuhiko@nexedi.com>

This reverts commit b2db18a0cb672204ff1dd9bc759934b332d433f5.

This contain the fix for go 1.16 that we backported, so we can use
upstream repository again

For now this still have to be enabled with a config like this in a .conf
file in srv/telegraf/extra-config/  :

    [[inputs.execd]]
      name_override = "slapos"
      # this needs sudo when using can not access supervisor socket, like when being installed in root slapos
      command = ["/usr/bin/sudo", "$SOFTWARE_DIR/go.work/bin/telegraf-input-slapos", "-config", "/path/to/slapos.conf"]

/path/to/slapos.conf would contain something like this:

    [[inputs.slapos]]
      ## Folder where partitions are located
      instance_root = "/srv/slapgrid/"

      ## filepath.Glob pattern to look for recursive instances
      recursive_instance_glob_pattern = "*/srv/runner/inst*/"

      ## Path of supervisor socket, relative to instance root
      socket_name = "sv.sock"

This version has a new sql input, that can be used to get metrics from sql
queries.

starting coverage in runUnitTest was too late, coverage has to be
started before anything is imported for correct reporting

Running test as last makes no sense nowadays, as the site is fully prepared.
Awaiting for each possible log of configured frontend is not worth the
requirement, so make those tests as first ones, which simplifies running only
them with reproducible effect.

All tests which could be affected by that fact has been identified and changed.

otherwise it probably uses system's openssl.

Setting rpath seems not needed because we are using
-DBUILD_SHARED_LIBS=OFF here.

https://github.com/sigoden/dufs

New software to serve static files

See merge request nexedi/slapos!1270

caddy-frontend-N is bad name, it's just frontend-node-N.

This option was useful only during the time, when there were experiments
running on caddy-frontend clusters during switch to HTTP/2.

Currently HTTP/2 is a standard, and there is no reason to disable it globally.

Attention, this change will require manual intervention on the upgraded
cluster with:

sed -i 's/^recipe = caddyprofiledeps/recipe = software/g' .installed*

On each partition.