Add CONFIG_MODULE parameter to CMake function. Add Tests for CMake Integration.

docs/source/usage/project_integration.md

mypy.ini

pyproject.toml

pytest.ini

src/pystencilssfg/cmake/modules/PystencilsSfg.cmake

tests/integration/cmake_project/.gitignore

tests/integration/cmake_project/CMakeLists.txt

tests/integration/cmake_project/GenTest.py

tests/integration/cmake_project/TestApp.cpp

tests/integration/cmake_project/gen_config.py

tests/integration/test_cmake.py