Cleanup and checking 02465 compatibility; thtools removed

src/coursebox/core/__pycache__/info.cpython-38.pyc

src/coursebox/core/__pycache__/info_paths.cpython-38.pyc

src/coursebox/core/__pycache__/projects_info.cpython-38.pyc

src/coursebox/core/citations.py

src/coursebox/core/info.py

src/coursebox/core/info_paths.py

src/coursebox/core/projects.py

src/coursebox/core/projects_info.py

src/coursebox/material/__pycache__/__init__.cpython-38.pyc

...al/__pycache__/homepage_lectures_exercises.cpython-38.pyc

...box/material/__pycache__/lecture_questions.cpython-38.pyc

src/coursebox/material/__pycache__/snipper.cpython-38.pyc

src/coursebox/material/homepage_lectures_exercises.py

src/coursebox/material/lecture_questions.py

src/coursebox/material/snipper.py

src/coursebox/thtools_base.py