Add `tests/utils/python/normand.py` (Normand 0.23)

Add `tests/utils/python/normand.py` (Normand 0.23)

This is an unmodified copy of the `normand.py` module [1], version 0.23.

Normand, an EfficiOS project, is both a template language to generate
binary data and a processor of said language.

`normand.py` is part of the `normand` package, but it's completely
independent, without external dependencies, therefore we can copy it
right here. `normand.py` works with Python 3.4. The module itself offers
a Python 3 API as well as a command-line tool.

We plan to use Normand in Babeltrace 2 to write human-readable and
Git-trackable plain text CTF data streams, and eventually other types of
binary data, for testing purposes.

Although Normand is an EfficiOS project, it's considered an external
project from the point of view of the Babeltrace project. Therefore, we
make Black, isort, and Flake8 ignore it, even though Normand uses the
same settings in its own repository.

[1]: https://github.com/efficios/normand

Signed-off-by: Philippe Proulx <eeppeliteloop@gmail.com>
Change-Id: I6e8937cf40320c3cf1226c3447f71640ed9f91bf
Reviewed-on: https://review.lttng.org/c/babeltrace/+/10910
Tested-by: jenkins <jenkins@lttng.org>
Reviewed-by: Simon Marchi <simon.marchi@efficios.com>