2023 update

[mariopesch]

• [ ] adjust Date
• [ ] add Call for Challenges
• [ ] add page for registration form
• [ ] add page for challenge form
• [ ] remove pre-event /replace with last year video
• [ ] update jury and prizes
• [ ] update mentors
• [ ] update timeline
• [ ] update faq with last year questions
• [ ] update organisators
• [ ] remove maxi from mailing
• [ ] link 2022 Projects and video (https://www.youtube.com/watch?v=UYpj-0ZbRpM)

to be continued