done with:

     npm install
     git ls-files | grep -v '\/unstable\/' | xargs ./node_modules/.bin/eclint fix
     git ls-files | grep buildout.hash.cfg | xargs ./update-hash

  The Remote User is managed on the backend apache which will unset it anyway.

As shown by https://github.com/zopefoundation/Zope/pull/655 and
https://github.com/Pylons/waitress/commit/6d4dab6bed88917b973066a6d5222917661802b7
backends usually don't accept headers with underscores.

SSL_CLIENT_SERIAL is removed because it's unused.

Include *.data and *.wasm files.
Which the content type is "application/wasm"

/reviewed-on nexedi/slapos!358

jinja2 template is required, as some paramters might come from the network.

/reviewed-on nexedi/slapos!345

/reviewed-on nexedi/slapos!346

Do not upper filenames nor users, use them as is.

/reviewed-on nexedi/slapos!339

No custom_http nor custom_https shall publish information normally calculated.

/reviewed-on nexedi/slapos!340

It was missing double slash (//) after schema.

/reviewed-on nexedi/slapos!332

The exposed apache_custom_http option for custom slave was
incorrectly missing, and apache_custom_http*s* was used instead.

/reviewed-on nexedi/slapos!330

_ (underscore) is not supported by apache as domain name
(https://bugzilla.redhat.com/show_bug.cgi?id=1410130), so avoid using it.

/reviewed-on nexedi/slapos!320

Since using apache-2.4[1] the Include directive will fail if no glob
matches, this switch to new, IncludeOptional[2], available since 2.4, in
order to not fail if no configurations are present.

 [1] 1f7bf3d1
 [2] http://httpd.apache.org/docs/2.4/mod/core.html#includeoptional

/reviewed-on nexedi/slapos!252

  This can be used to define minimal metrics to the frontend to
  prevent mpm nodes starvation after gracefull restarts

  Wait for 60 to reload apache configuration in order to accumulate
  several logrotate runs.

  If the amount of slaves are too high, the number of logs are high,
  so the entries on logrotate are also high. So it is enough to DDoS
  with a huge amount of 'kill -1', so delay is the only way to avoid
  to re-implement logrotate existing features.

  Only reload the apache configuration if the the apache configuration
  or the certificates contains a change, else don't reload it.

  Keep a command on bin folder to force reload of configuration in
  case it is required.

  Allow http2 protocol be enable or disable by default
  Allow set certain configurations for MPM to control the number of process and threads.

  Apache verbose way too much with LogLevel info

  When slow clients post a large request, 30 seconds is too short for the current
  production usage. Short timeouts are rare but it always happens on POST, which
  is annoying for the user.

  Move from 30s to 5min the timeout to allow the slow clients upload their data
  with time.

  It is protected with monitor password.

This reverts commit b4e440ed

If not so, trafficserver configuration is removed and then replaced on
every slapos node instance call making traffic server unstable

  Introduce NGINX on the same partition of apache to handle websocket\
  and eventsource types.

  The NGINX will run on another port and it would require a second ip at
  the machine for enable it.

  This configuration is a working version with fully https support, but
  some additional adjustments might be required.

  Use a single apache server to handle cache and normal apache configurations. With trafficserver,
  the access would follow the model:

    Apache > Traffic Server > Apache 'Cache' > Backend

  Now the configuration changed to:

    Apache > Traffic Server > Apache (same as before) > Backend

  This simplify the amount of apache process to manage on the frontend.

  Reduce a bit the number of sections also for create directories
  Move all 'set's and 'do's to earliest as possible, to keep buildout syntax more evident
  Drop duplicated logics and 'if's reducing general code