Add working example of environment based time zones

[emmuhamm]

Description

Fix #70

Add better timezone handling. This is going to be optionally done by an environment variable, which overrides the log_format.ini settings.

Add better theme handling. This is also going to optionally done by an environment variable, which overrides the log_format.ini settings.

For full explanations, please see the docs in this PR, and also the testing notes

Testing notes

Tested on latest nightly (doesnt matter which)

Run
export DUNEDAQ_TIMEZONE="Europe/London"
export DUNEDAQ_LOGGING_THEME="dark"

and
daqpytools-logging-demonstrator -r

See how the colors and the timezones has changed. Play around with various timezones and themes.

When finish, run
export DUNEDAQ_TIMEZONE=""
export DUNEDAQ_LOGGING_THEME=""
And see how they revert back to their default behaviour

TODO:

• Figure out why it breaks integ test if different timezone is chosen (likely outside scope of this PR)

Type of change

• New feature or enhancement (non-breaking change which adds functionality)

Testing checklist

• Unit tests pass (e.g. dbt-build --unittest)
• Minimal system quicktest passes (pytest -s minimal_system_quick_test.py)
• Full set of integration tests pass (dunedaq_integtest_bundle.sh)
• Python tests pass if applicable (e.g. python -m pytest)
• Pre-commit hooks run successfully if applicable (e.g. pre-commit run --all-files)

Comments here on the testing

Further checks

• Code is commented where needed, particularly in hard-to-understand areas
• Code style is correct (dbt-build --lint, and/or see https://dune-daq-sw.readthedocs.io/en/latest/packages/styleguide/)
• If applicable, new tests have been added or an issue has been opened to tackle that in the future.
  (Indicate issue here: # (issue))

[emmuhamm]

There appears to be a very stupid bug somewhere in the integ test..

Note in the following screenshots, when it is in UTC everything works well. But when its in some other time zone (eg bst) then it fails????

Obviously outside the purview of daqpytools, but it should at least still be investigated.

[emmuhamm]

How to view timezones

In [40]: import pytz
In [41]: pytz.all_timezones

[emmuhamm]

Noticed a bit of clarity I can stick in here while im updating the docs anyway

[emmuhamm]

@PawelPlesniak review pls :)

When this is all good and merged, I'll let kurt know about this

[PawelPlesniak]

I would suggest having a line stating something along the lines of

If a non-default time zone/theme is preferred, it is recommended to set the env vars DUNEDAQ_TIMEZONE and DUNEDAQ_LOGGING_THEME in your ~/.bashrc

Also non-review note, reading the black theme in a black terminal is impossible XD

[PawelPlesniak]

Small comment, but other than that, nice work!