Allows to use recipe for cases when file is not present yet so it can return
some default (marker-like) value.

1.0.181 cannot be installed on Debian 11

This reverts commits d23929f7
(partially) and 3c52286b.

This issue is in slapos.core, slapos/testing/check_software.py:

      '*/parts/libreoffice-bin/*',
      '*/parts/java-re*/*',

We'll reapply the changes after (or at the same time as)
slapos.core is updated.

Make the md5 detection fix python3 compatible.

Fixes 4e5a9ee4

In addition to update version of slapos.recipe.build, this fixes the
following misuse:
- init phase must only initialize the section, which implies no change
  on the file system
- init/install/update's slapos.recipe.build should not contain buildout
  substitutions (theoritically, there could be wrong escaping,
  e.g. ${buildout:directory} containing quotes)
These 2 points didn't not matter here but it gave a bad example
for anyone learning buildout.

Thanks to the new buildout/slapos.recipe.build feature,
we can download the last released version of Debian Stable.

NEO stress testing is changed to run on both Debian 10 & 11.

Keep proposing Debian 10 netinst in kvm SR,
waiting that Debian 11 is more tested.

This fixes build of gevent on recent OS, due to missing greenlet
header file for Python 2.

- Clean up patch, mainly to not hardcode the fact that the recipe
  uses __compile__ suffix for build directory.
- Do not install *.o; install executables in bin/
- The URL didn't work anymore: switch to another one.

Each node requests a frontend instance used to publish information about
itself, but there was missing a promise on the node itself, if the frontend
instance is operational. Even if there is global cluster check of those
information, it does not trigger node reprocessing, thus adding additional
promise on each node.

For case if path (for zope) is provided from
/VirtualHostBase/https//example.com:443/zope_path/VirtualHostRoot/url_path
to
/VirtualHostBase/https/example.com:443/zope_path/VirtualHostRoot/url_path

If path (for zope) is not provided from

/VirtualHostBase/http//example.com:443//VirtualHostRoot/url_path
to
/VirtualHostBase/http/example.com:443/VirtualHostRoot/url_path

With Theia 1.17.2 we remain stuck on the loading page.

This reverts commit 6103d29a.

Instead of using complex mechanism with slaves (which are not monitored
anyway), allow the user to express monitoring with simple UI on normal
instance.

Additionally support for simple domains, not only URLs, is added.