Add restrictive firewall settings to avoid any security risk.

Bug appeared due to wrong pip version. Therefore the version has been
set explicitly.

Now the Python script name is consistent with the file name in the
Fluentd config file as described in the learning track.

Should be installed via rapid.space panel.

Previously it failed because setuptools wasn't installed.

Replaced 'computer_name' with 'computer_id'. Previously I confused both.
Now the user has to enter the respective computer reference.

It won't run in an issue anymore if the file already exists.

Fluentd couldn't be installed because we first have to configure the
SlapOS client via `slapos configure client` before being able to use
`slapos console` (to supply and request Fluentd from a Python script).

In the Wendelin learning track this permission is granted to the user via
"chgrp SLAPUSER /dev/i2c-3". Because we don't know the particular
slapuser we have to add the permission to all users of the slapsoft
group. Because /sys/bus/i2c/devices/i2c-3 is a virtual directory and
we want to make sure that even after rebooting or unplugging /
replugging of the sensor the permission is still granted udev rules
have been added.

Initial commit for adding automatic preperation of Olimex boards as an IoT Gateway
and for a Sensor to send data to Wendelin (see
https://wendelin.nexedi.com/wendelin-Learning.Track/wendelin-Tutorial.Setup.Sensor.IOTGateway/WebPage_viewAsWeb
).

Since tests are launched inside namespace, we don't have SUID ping
available anymore so we explicitely allow all users to do ping.

Please note that this works for both IPv4 and IPv6 despite the name.

See nexedi/slapos!1107 (comment 148968)
for more information.

While bootstraping a host, the network can be in unknown state, and a
lot of tasks depend on the network, thus make sure that network is
available.

By extracting the hostname task to vm-bootstrap-hostname it's possible
to setup it as a dependency role for vm-bootstrap, before package role,
which depends on the network setup.

For KVM version < 1.0.220, the script /etc/opt/netconfig.sh is doing:

1) add address on IFACE
2) add routes going through IFACE
3) set IFACE up

But we can't add routes to an interface which is down. So call the
script twice so that the routes are really added during the second run.

The fix for KVM can be found at nexedi/slapos@07439e2e

slapos.cfg example is maintained in slapos.core and available at
/opt/slapos/eggs/slapos.core-*.egg/slapos/slapos.cfg.example

Also make vm-bootstrap role depends on python3

It was always done like this but has been removed in a previous cleanup (c7183d54). No need anymore for the upload.yml playbook.