Website/repo maintenance

[ch1pkav]

1. Add links to all the presentations to the corresponding week entries in the repo and website homepage:
   • Week 0 Intro presentation
   • Week 1.1 Open source presentation
   • Week 1.2 Package managers presentation
   • Week 2 CLI presentation
   • Week 3 Git, GitHub presentation
   • Week 4 Vim + tmux presentation
   • Week 5.1 LFHS presentation
   • Week 5.2 RegEx presentation
   • Week 6. Partitions, bootloaders presentation
   • Week 7. Filesystems presentation
   • Week 8. SSH presentation
   • Week 9. Kernel, systemd (TBD)

Check that all of them have rights for viewing by link, outside of UCU domain (a surprising number of people tend to refer to this website outside UCU). Weeks 9-11 are not yet done, so they may go without links for now.

2. Remove all links to the youtube channel in the repo and website, most importantly from the website footer:

[rwmutel]

done