Fixes:
- Updates packer version
- Updates packer-plugin-arm-image name
- Downloads packer plugin via packer CLI instead of building from source
- Supports image builds on more machines by downloading the correct
  packer release for the current build machine's CPU type
- Dependencies added to 'image' target to ensure that packer is installed
  and that the image is only rebuilt when the input files are updated
- Prevents Ansible from changing build machine's hostname

Signed-off-by: llamasoft <[email protected]>

Raspbian has been deprecated in favor of RaspiOS.
As a consequence, the Raspbian repo has changed from 'stable' to 'oldstable'
which causes the apt-get update command to fail.  This is the minimal change
required to get the outdated image to build correctly.

Signed-off-by: llamasoft <[email protected]>

The PGP signature file for the re4son-kernel repo expired on August 29, 2022.
The re-signed PGP key is available from the MIT PGP keyserver.

Signed-off-by: llamasoft <[email protected]>

flask, Jinja2, Werkzeug, and itsdangerous are all from Pallets Projects
who seemingly refuse to use PEP-440's ~= "compatible release" clause.
Instead, all of their project dependencies are ">=" which eventually
causes things to break.
Their canned response is to recommend always staying on the latest version
and to use something like pip-tools to pin dependencies.
pallets/markupsafe#282 (comment)

Signed-off-by: llamasoft <[email protected]>

Raspbian has been renamed to Raspberry Pi OS.
RasPiOS on buster is considered legacy but images are still released for it.
A few packages have to be uninstalled (from the main repo) and
reinstalled (from the re4son-kernel repo) to fix dependency issues.

Signed-off-by: llamasoft <[email protected]>

The default ARM CPU emulated by qemu is armv7l.  While this is fine for most packages,
it leads to the wrong opencv and tensorflow being installed.  By emulating the correct
CPU, we're guaranteed to end up with the correct binaries.

Signed-off-by: llamasoft <[email protected]>

If the monitor interface is created before the wlan0 interface is up,
the resulting mon0 interface will be in a permanently broken state.
Since the "[email protected]" is disabled and getting timing guarantees
from systemd is a challenge, we manually up the interface.

Signed-off-by: llamasoft <[email protected]>

An interface in static mode is required to have an address defined,
otherwise ifup will throw an error and fail to bring the interface up.
The Debian wiki provided the pre-up/post-down solution:
https://wiki.debian.org/NetworkConfiguration#Bringing_up_an_interface_without_an_IP_address

Signed-off-by: llamasoft <[email protected]>

The installation of system files has been moved into the 'install' command
instead of running unconditionally.  This makes it possible to create a source code
distribution of that doesn't immediately clobber the build machine's system files.
This will also allow the image build to be simplified as it will only need to copy the
sdist archive instead of multiple directories worth of files.

Signed-off-by: llamasoft <[email protected]>

The idea here is that the requirements.in file should be the loosest allowed
requirements for the project itself, then it should be pip-compile'd into
a concrete requirements.txt that has known working values.  This prevents
unnecessarily pinning packages to specific releases which makes it easier
to keep package versions up-to-date going forward.

Signed-off-by: llamasoft <[email protected]>

Firstly, all requirements were sorted.  Then, any dependencies not directly
used by pwnagotchi were removed (e.g. gast isn't used directly, but it will
eventually be installed as an indirect dependency of tensorflow).
Next, every single dependency was researched and documented to determine how
it's used in addition to what versions it can be safely upgraded to.
Most dependencies have been updated to use the PEP-440 "compatible release" feature.
Lastly, the --extra-index and --prefer-binary options have been added.
As a result of some unfortunate publication issues (e.g. grpcio v1.46.X),
some non-yanked libraries simply cannot be built from source.
The --prefer-binary option allows pip to prefer an older library version if
it has a binary wheel available.  This also results in faster builds as
fewer requirements actually need to be compiled from source.

Signed-off-by: llamasoft <[email protected]>

In theory, this file shouldn't need to be regenerated very often.
One thing of note is that pip-compile strongly recommends that it be run
on the target system in order to ensure it selects the correct versions.
This is because pip-compile doesn't (yet) have a way to specify the
Python version, platform, and machine type during compilation.
The setup.py file was also tweaked to ignore any --options in the
requirements.txt file.

Signed-off-by: llamasoft <[email protected]>

Despite the fact that a headless version of opencv exists,
stable-baselines and gym both request the regular opencv which
has a dependency on libgtk3 despite the fact that they don't use
any of the GUI functionality.

Signed-off-by: llamasoft <[email protected]>

Installing pwnagotchi using the local sdist has a few key benefits:
- We're no longer installing all of the data files twice,
  once in packer and once in the setup.py script.
- The image is built using the code in the current local repo,
  not whatever code is currently pushed to the remote master branch.
  This makes it much easier to create and test custom images.
- Installs pwnagotchi using pip, just like the auto-update plugin does.

Signed-off-by: llamasoft <[email protected]>

As the added comments describe, the options available to us from Ansible's
apt module don't actually clean the apt cache.
Manually running apt-get clean recovers around 400MB of space.

Signed-off-by: llamasoft <[email protected]>