createCallback is used in pbs recipe.

The function was wrongly removed in
569439d5.

Former URL of models is now 404. Thus use proper offcial github location (no change of md5sum of file).

As we can see in the testcases added, since we started to use Firefox 60, fonts were no longer selected and some garbage characters were displayed instead of the text.

Before these changes, it looked like this:

![screenshot_test.TestFirefox60.test_screenshot_before](/uploads/7ffe2eb7678b9f62ae13a56f4c8b57cf/screenshot_test.TestFirefox60.test_screenshot_before.png)

now it looks like this:

![screenshot_test.TestFirefox60.test_screenshot_after](/uploads/6d178ebdac388e534206149e97de08a1/screenshot_test.TestFirefox60.test_screenshot_after.png)

which is of course better, but still wrong, because the test case uses Arial and this font is not Arial. This part will be fixed later.

It seems firefox no longer accepts fonts from slapos directories, before the fix, firefox prints this on console:
    
    (./parts/firefox-60/firefox:7277): Pango-WARNING **: 08:06:33.942: failed to create cairo scaled font, expect ugly output. the offending font is 'IPAGothic 9.9990234375'
    (./parts/firefox-60/firefox:7277): Pango-WARNING **: 08:06:33.942: font_face status is: file not found
    (./parts/firefox-60/firefox:7277): Pango-WARNING **: 08:06:33.942: scaled_font status is: file not found
    (./parts/firefox-60/firefox:7277): Pango-WARNING **: 08:06:33.942: shaping failure, expect ugly output. shape-engine='PangoFcShapeEngine', font='IPAGothic 9.9990234375', text='?'
    (./parts/firefox-60/firefox:7277): Pango-WARNING **: 08:06:33.943: failed to create cairo scaled font, expect ugly output. the offending font is 'IPAGothic 9.9990234375'
    (./parts/firefox-60/firefox:7277): Pango-WARNING **: 08:06:33.943: font_face status is: file not found
    (./parts/firefox-60/firefox:7277): Pango-WARNING **: 08:06:33.943: scaled_font status is: file not found

but the file exists... Maybe this is a bug in firefox ( https://bugzilla.mozilla.org/show_bug.cgi?id=1336049#c2 looks similar, even though for us in firefox 52 it was fine and the problem appeared between 52 and 60).

A simple workaround is to copy all fonts in firefox fonts' directory.

See merge request !736

${xvfb-instance:display} is used in in runTestSuite.in

"bin/pythonwitheggs" no longer exist

See merge request !738

"bin/pythonwitheggs" no longer exist

See merge request !737

This makes firefox 60 and 68 able to load some fonts and fixes the issue
that fonts were rendered as garbled text

This fixes a regression from merge request !729 , surykatka command was
no longer installed

This code have been moved to slapos.core

- not all SR was using Cython 0.28.2
- with an upcoming upgrade of pycocotools, matplotlib>=2.1.0 will be required

in some webrunner, there are 2 keys in equeue.db:

```
>>> print(db.keys())
['/srv/slapgrid/slappart18/bin//runner-importer', '/srv/slapgrid/slappart18/bin/runner-importer']
```

As you can see, the importer script path changed. But we don't care
about this, we always want to have the latest (= the newest) backup date.

See merge request !734

in some webrunner, there are 2 keys in equeue.db:

```
>>> print(db.keys())
['/srv/slapgrid/slappart18/bin//runner-importer', '/srv/slapgrid/slappart18/bin/runner-importer']
```

As you can see, the importer script path changed. But we don't care
about this, we always want to have the latest (= the newest) backup date.

Because of a bug in `slapos/testcase`, ldd check was not properly reporting several problems, because several components were using system libraries.

These are the changes to profiles, adding the missing rpath and other changes so that components do not use system libraries either by explicitly providing the libraries so that the configure script does not use system development libraries if they are available ( like for zstd ) or by disabling the features at compile time for features we don't use ( like the `--without-icu` for boost )

See merge request !732

Fix this random failure we sometimes have, like [here](https://nexedijs.erp5.net/#/test_result_module/20200414-44DF7D23/11) by adding a promise so that test does not try to connect to a nginx that's not started yet

```
======================================================================
ERROR: test (test.TestJSTestNode)
----------------------------------------------------------------------
Traceback (most recent call last):
  File "parts/slapos-repository/software/jstestnode/test/test.py", line 60, in test
    '%sjio/test/tests.html' % (connection_dict['nginx'], ), allow_redirects=False)
  File "eggs/requests-2.20.0-py2.7.egg/requests/api.py", line 75, in get
    return request('get', url, params=params, **kwargs)
  File "eggs/requests-2.20.0-py2.7.egg/requests/api.py", line 60, in request
    return session.request(method=method, url=url, **kwargs)
  File "eggs/requests-2.20.0-py2.7.egg/requests/sessions.py", line 524, in request
    resp = self.send(prep, **send_kwargs)
  File "eggs/requests-2.20.0-py2.7.egg/requests/sessions.py", line 637, in send
    r = adapter.send(request, **kwargs)
  File "eggs/requests-2.20.0-py2.7.egg/requests/adapters.py", line 516, in send
    raise ConnectionError(e, request=request)
ConnectionError: HTTPConnectionPool(host='::1', port=9443): Max retries exceeded with url: /jio/test/tests.html (Caused by NewConnectionError('<urllib3.connection.HTTPConnection object at 0x7f9b01f4b310>: Failed to establish a new connection: [Errno 111] Connection refused',))

```

See merge request !733

Several software use `slapos` command and expect this command to have networkcache support enabled, which is achieved in buildout by having `slapos.libnetworkcache` in the egg "working set" when generating the slapos script.

Introduce a dedicated section to install `slapos` command and use it in softwares which includes a slapos, testnode and slaprunner. Test softwares like slapos-sr-testing also need a slapos command, but they generate one with development version of slapos.core.

Before these changes, several software were installing `slapos` indirectly by installing `extra-eggs` from monitoring stack. The monitoring stack was also modified so that it uses a section with a prefix (`monitor-eggs`) and users of monitoring stacks were also modified to not use this `extra-eggs` part from monitoring stack, but install eggs through their own section.

Similar problem also existed with `slapos.toolbox`, which is installed by several softwares and stacks, for different reasons (because it contains lots of utilities), now that buildout detects parts installing the same path, only one parts can install the scripts. For this, define a section `slapos-toolbox` that software and stack should install, instead of listing the egg as `eggs` in a `zc.recipe.egg` section, because that would install the scripts again.

See merge request !729

When we have a section to generate a python interpreter with eggs built
in, don't name this `extra-eggs` because the meaning is not clear.

This section installs slapos.toolbox eggs with dependencies and install
scripts

Despite the name, this section was inherited from monitor, but now that
we fixed monitor to prefix the sections, this section is no longer
extended from monitor, but defined in softwares

Also build the binaries as static so that they don't use system
libraries.

To prevent using system libraries

Otherwise it will try to use development system package and we will have
different results depending on wether that package is installed or not.

Note that because of a typo in the environment variable (this makefile
uses $LDFLAGS, slapos zlib was not effective so far)

slap_connection is deprecated