Release v1.2.0

Changelog between v1.1.1 and v1.2.0:

 .github/workflows/main.yml             |  9 +++++++++
 .gitignore                             |  3 ++-
 README.rst                             |  6 ++----
 docs/conf.py                           | 18 +++++++++++-------
 docs/source/readme_full.rst            | 22 ++++++++++------------
 lbh15/__init__.py                      |  7 +++----
 lbh15/{_constants.py => _commons.py}   |  5 +----
 lbh15/_lbh15.py                        | 11 ++++++-----
 lbh15/bismuth.py                       | 11 ++++++-----
 lbh15/lbe.py                           |  9 +++++----
 lbh15/lead.py                          |  9 +++++----
 lbh15/properties/bismuth_properties.py | 34 +++++++++++++++++-----------------
 lbh15/properties/interface.py          | 12 ++++++------
 lbh15/properties/lbe_properties.py     | 34 +++++++++++++++++-----------------
 lbh15/properties/lead_properties.py    | 36 ++++++++++++++++++------------------
 pyproject.toml                         | 40 ++++++++++++++++++++++++++++++++++++++++
 setup.py                               | 96 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++--------------------------------------
 tests/custom_properties/properties.py  |  6 +++---
 tests/test_lbh15_bounds.py             |  6 +++---
 19 files changed, 222 insertions(+), 152 deletions(-)