ZSK teachers' and classrooms' timetables scraper

1. The ready-to-use timetables are located in JSON/timetables
2. Main code is, of course, in main.py
3. plain_text_solution.py is just a file to make easier preparing plain_text_solution.json, which must be done by hand (as far as I know, if anybody has other idea than asking AI I'd be pleased to hear it)
4. files teachers.json and lessons.json are the same case as above, but without .py version (it might be added in the future)

P.S. Remember to run the scripts from /planyn directory, otherwise relative imports go outside the window