Unless we think of something else to add, this version of the docs
is suitable for the 6.2 release.

Fixes #2943

Patch by @phk, test by yours truly.

See dd28fc73 for the whole story.

Dealing with code style violations around the return keyword, I figured
I could automate that fix, so I tried with my favourite refactoring tool
and following those steps:

    $ cat >return.cocci <<EOF
    @@
    expression rv;
    @@

    - return rv;
    + return (rv);
    EOF
    $ spatch --dir . --in-place --sp-file return.cocci

Unfortunately that leads to proper return statements having their return
value enclosed twice, like `return ((rv))`. So a bit more steps to go:

    $ cat >rereturn.cocci <<EOF
    @@
    expression rv;
    @@

    - return ((rv));
    + return (rv);
    EOF
    $ spatch --dir . --in-place --sp-file rreeturn.cocci

At this point you don't want to touch bundled code, right? So let's take
care of libvgz and shout out to teken that saw no changes at all!

    $ git checkout -- lib/libvgz/

The next step is to manually review all the changes, because Coccinelle
is not aware of how we break lines and unbreaks them. That's quite
tedious but I was waiting for someone and they are still late as I'm
describing the whole process.

Care was taken not to touch varnishtest to make it easier to sync with
vtest. A dedicated patch will follow.

Pointed out by:	slink

At this point someone should take care of removing instructions for
changes and upgrading documents authors to make sure they don't end
up in the release.

Instructions in doc/sphinx/installation/install.rst also need a
serious refresh for all platforms and interested parties should take
care of the platforms they are familiar with.

For a given definition of "future" or "now".

Until the naked "python" executable refers to python3 (currently it is
still python2) it now takes lower precedence.

and return a 500 for that instead of panicing in VSB.

Fixes #2938

Ref 8be771d1
Ref #2932

Note: This does not consitute a change, we had just missed to document
the values in use previously (except for workspace_backend which I will
add to the release notes).

Ref #2932

Ref #2932

Closes #2932

Ref #2932