Chaging file structure to accept -e flag with pip install

[hvsouza]

Issue

Installing dune_ploy_style with -e flag fails. The installation itself does not fail, however, the examples will not work with the following message:

AttributeError: module 'dunestyle.matplotlib' has no attribute 'OffWhiteBackground'

Hint of the problem

When installing with python -m pip install -e . -v the following messages shows up:

/tmp/pip-build-env-y1gqtteg/overlay/lib/python3.12/site-packages/setuptools/command/editable_wheel.py:352: InformationOnly: Editable installation.
  !!

          ********************************************************************************
          Please be careful with folders in your working directory with the same
          name as your package as they may take precedence during imports.
          ********************************************************************************

  !!
    with strategy, WheelFile(wheel_path, "w") as wheel_obj:
  Building editable for dune_plot_style (pyproject.toml) ... done
  Created wheel for dune_plot_style: filename=dune_plot_style-1.2-0.editable-py3-none-any.whl size=9937 sha256=8b872ff8de004de075dd8960cbc16d04532516e9679c6dc3956e20e51e26ff1d
  Stored in directory: /tmp/pip-ephem-wheel-cache-796kcggc/wheels/58/b6/a0/98ae73e188d6965b5a8ffb64175427854315aeb5102c45ad78

Fix

To fix the issue, I've restructured the folders in order to have codes with different naming.

Notes:

I created as a draft because I am not expert on creating packages, etc. I went back and foward trying to find a solution and this was the only thing that worked.

Tested with Python, ROOT and PyROOT:

• python 3.9.12 and 3.10.10

• ROOT Version: 6.30/02
  Built for linuxx8664gcc on Dec 20 2023, 19:16:00
  From heads/master@tags/v6-30-02

All tests in lxplus

[hvsouza]

I have updated the root-cpp-example in order to work with the new files tree.

I added a .gitignore to avoid mistakes like my with pycache and others.