XXX delete not needed possibly

See merge request nexedi/slapos!839

https://github.com/eclipse-theia/theia/blob/v1.7.0/CHANGELOG.md#v170---29102020

Future Cython+ work will use it.

Fix for #20200514-218C705 - \[testnode\] frontend for log access

Depends on nexedi/erp5!1304

See merge request nexedi/slapos!848

This fixes the nextcloud SR, which was broken by
commit 92779bf4
(mariadb is not a part anymore).

This fixes commit a62e5e7b.
See also commit 491e6e28.

And set it as log_frontend_url in testnode config

Just add the following 2 lines in a SR:

[mariadb]
location = ${mariadb-10.4:location}

It does not build with GCC 8.2

Going Go1.14.9 -> Go1.14.10 brings in compiler and runtime fixes
including fix for crash in garbage-collector due to race condition:

https://github.com/golang/go/issues/40642
https://github.com/golang/go/issues/40641

Tested on helloworld SR.

See merge request nexedi/slapos!844

validators.url is enough, even for Caddy, to check that URL is correct, and
caddy_backend_url_validator was introduced before validators.

Also calling an external command for each slave takes a lot of time.

Thanks to this other sections can directly reference them, and so they are
correctly created as needed, so linking section does not need update-command

The password is anyway present in the section itself, so it's eventual change
will result with reinstalling the section.

Also change a bit existing frontend_url to manage it the same way.

This way buildout can reuse egg caches and it's a bit faster:

To run a simple instance buildout, from 2.837s it goes down to 1.875s.
To run slapos node instance 10 times just after requesting an ERP5 instance, it goes from ~112s to 98s

before:

    hyperfine "/srv/slapgrid/slappart4/srv/slapos/inst/slappart0/tmp/shared/python2.7/60364a13cc977dd5a894e0239ac889b9/bin/python2.7 /srv/slapgrid/slappart4/srv/slapos/inst/slappart0/tmp/soft/c63ba7265399450b28f9ea6d5667a5e7/bin/buildout -U"
    Benchmark #1: /srv/slapgrid/slappart4/srv/slapos/inst/slappart0/tmp/shared/python2.7/60364a13cc977dd5a894e0239ac889b9/bin/python2.7 /srv/slapgrid/slappart4/srv/slapos/inst/slappart0/tmp/soft/c63ba7265399450b28f9ea6d5667a5e7/bin/buildout -U
      Time (mean ± σ):      2.837 s ±  0.275 s    [User: 2.481 s, System: 0.285 s]
      Range (min … max):    2.482 s …  3.222 s    10 runs

after:

    hyperfine "/srv/slapgrid/slappart4/srv/slapos/inst/slappart0/tmp/shared/python2.7/60364a13cc977dd5a894e0239ac889b9/bin/python2.7 /srv/slapgrid/slappart4/srv/slapos/inst/slappart0/tmp/soft/c63ba7265399450b28f9ea6d5667a5e7/bin/buildout -U"
    Benchmark #1: /srv/slapgrid/slappart4/srv/slapos/inst/slappart0/tmp/shared/python2.7/60364a13cc977dd5a894e0239ac889b9/bin/python2.7 /srv/slapgrid/slappart4/srv/slapos/inst/slappart0/tmp/soft/c63ba7265399450b28f9ea6d5667a5e7/bin/buildout -U
      Time (mean ± σ):      1.875 s ±  0.067 s    [User: 1.660 s, System: 0.148 s]
      Range (min … max):    1.816 s …  2.038 s    10 runs

See merge request nexedi/slapos!846

Changes configuration files to run repman tests in python3.

Adds the newly added to nexedi's repositories rubygemsrecipe (https://lab.nexedi.com/nexedi/rubygemsrecipe) to the list of tested eggs.

This also fixes rpath of rust binaries.

See merge request nexedi/slapos!845

When proftpd software release is tested locally, the socket named /srv/slapgrid/slappart76/srv/runner/instance/slappart1/tmp/soft/91d420e3970a2088e648d2eb86e155ea/parts/prof is created but never removed.
First it is not an appropriated directory to create a socket and then not removing this socket leads to an error if tests are run a second time :

subprocess.CalledProcessError: Command '('ldd', '/srv/slapgrid/slappart76/srv/runner/instance/sla
ppart1/tmp/soft/91d420e3970a2088e648d2eb86e155ea/parts/prof')' returned non-zero exit status 1.

----------------------------------------------------------------------
Ran 0 tests in 9.914s

FAILED (errors=1)

This is due to code in https://github.com/proftpd/proftpd/blob/master/src/ctrls.c :

const char *socket_path = PR_RUN_DIR "/test.sock"; // socket_path="/srv/slapgrid/slappart76/srv/runner/instance/slappart1/tmp/soft/91d420e3970a2088e648d2eb86e155ea/parts/proftp/var/test.sock"
sstrncpy(sockun.sun_path, socket_path, sizeof(sockun.sun_path)); // sockun.sun_path="/srv/slapgrid/slappart76/srv/runner/instance/slappart1/tmp/soft/91d420e3970a2088e648d2eb86e155ea/parts/prof"

where `sun_path` is limited to UNIX_PATH_MAX (108 characters): char sun_path[UNIX_PATH_MAX]; https://elixir.bootlin.com/linux/latest/source/include/uapi/linux/un.h#L9

See merge request nexedi/slapos!838

We don't plan using varnish like this.

Move `numpy=1.16.4` from all over the place into component/numpy.
Don't move if a different numpy version is used, or it looks like a
software cares to use exactly particular version.
Downgrade pygolang/test.cfg from numpy=1.16.6 to numpy=1.16.4 and use
common numpy component version - using numpy=1.16.6 is not required for
pygolang testing and so this downgrade is acceptable. It will be better
to upgrade NumPy to latest in component/numpy/ as a future separate step.

See previous patch where it was decided and explained that version for
component <X> lives in component/X/.

Move versions for eggs that component/{ZEO,pygolang,zodbtools,pytest}
depend on out of component/ and into stack/slapos.cfg

Leave version of component <X> inside component/<X>.

I was asked to do so:

nexedi/slapos!839 (comment 119170)

I tried to use this gdb in a software release installed by slapos-sr-testing (which perform some extra checks that we only do in slapos-sr-testing at the moment) and it complains that:

```
======================================================================
ERROR: setUpModule (test)
----------------------------------------------------------------------
Traceback (most recent call last):
  File "/srv/slapgrid/slappart9/srv/slapos/soft/24930952d96110d7e0142b49eba918a8/parts/slapos.core-repository/slapos/testing/testcase.py", line 168, in setUpModule
    installSoftwareUrlList(cls, [software_url], debug=debug)
  File "/srv/slapgrid/slappart9/srv/slapos/soft/24930952d96110d7e0142b49eba918a8/parts/slapos.core-repository/slapos/testing/testcase.py", line 378, in installSoftwareUrlList
    checkSoftware(cls.slap, software_url)
  File "/srv/slapgrid/slappart9/srv/slapos/soft/24930952d96110d7e0142b49eba918a8/parts/slapos.core-repository/slapos/testing/testcase.py", line 336, in checkSoftware
    raise RuntimeError('\n'.join(error_list))
RuntimeError: /srv/slapgrid/slappart9/srv/slapos/inst/slappart7/tmp/shared/gdb/d14016b094c3637c4ebf6a3df4a8c64d/bin/gdb uses system library /usr/lib/x86_64-linux-gnu/libexpat.so.1.6.8 for libexpat.so.1

----------------------------------------------------------------------
Ran 0 tests in 462.686s
```

I saw this on a debian KVM on which I don't think I installed any system package except `slapos-node`, but `libexpat1-dev` is installed for some reason, so configure detected it and the built binary is linked against it. I checked some test nodes and `/usr/include/expat.h` seems present on some testnodes, so probably some test nodes will also have this problem. For that, I suggest to build a gdb using slapos `libexpat`, so that we build something more reproductible and not depending on the host system (that's important if we want to use binary cache, but can also be a problem if system packages get remove/upgraded). As you might be thinking now, that's a kind of infinite problem, because we can not add anything that configure might detect, but that's how we usually do for this for now.

While looking at this, I also realised that we were using a .tar.xz URL here, for which rely our recipe will use `xz` command. Because some machines might not have that command, we usually put `xz-utils` in PATH.

How about including something like this ?