Remove existing "embedded instance" options:
- `embedded-sr`
- `embedded-sr-type`
- `embedded-instance-parameters`

Instead introduce `one-time-embedded-instance` option:
- Only taken into account when Theia is instantiated the first time.
- Content should be a JSON object with:
  - 'software-url': string of the software URL
  - 'software-type': (optional) string of the software type
  - 'instance-parameters': (optional) JSON object

If the option is non-empty:
- Theia will attempt once to:
  - Parse the JSON content
  - Create a supply/request script
  - Call the script
- A promise will check whether the script was successfully called.

If the promise fails forever, e.g. because of ill-formed JSON, emptying
the option will remove the promise. Editing the option after the first
time will have no effect, whether the promise succeded or not.

Use slapos.recipe.template instead of slapos.recipe.template if possible

Harmonize template keys :
rendered -> output
template -> url
template = inline: -> inline =

Delete "mode" key

See merge request !1151

The egg slapos.core is now used with python3 by default (except in slaprunner).

See merge request nexedi/slapos!1154

slaprunner is actually not working in python3 (see
nexedi/slapos.toolbox!103)
and is currently unmaintained.

theia, erp5testnode are both running a slapos standalone. We don't
change slaprunner to python3 because it's not maintained anymore and
should disappear in the near future.

After removal of git server in f3dc178f,
no need for mod_cgid anymore.

Also, the mod_cgid was reporting an error because ScriptSock was not set
so the socket file was created in the software compilation folder:

[cgid:error] [pid 109996:tid 139713924945728] (13)Permission denied: AH01243: Couldn't bind unix domain socket /srv/slapgrid/slappart71/srv/runner/shared/apache/81977b7512b75d38df008fc5ede74d94/logs/cgisock.105061

Use the exact version number displayed on the pypi index, because our shacache system is based on the URL which contains a package version number.

See merge request nexedi/slapos!1134

New software release for https://github.com/beremiz/beremiz.

IDE require X server with libvncserver and x11vnc to work and can be used
in a browser with deployed NoVNC.
Runtime deployed can be used to executes PLC program.

The software release is also used to run Beremiz IDE tests using sikuli and unittests

Set in preferences the path of this interpreter, for example:

```json
{
  "python.pythonPath": "/srv/slapgrid/slappart19/srv/runner/software/91be79296dea036ad98d4aff08ecb74b/bin/python"
}
```

then when editing products files completions and jump to definition should work. It works but it is sometimes so slow that it seems not working.

See merge request nexedi/slapos!1153

This macro generates an intepreters knowing its own sys.executable, so
it can be used as interpreter for theia's python extension to provide
code navigation, completion etc.