Update after the course of may 2024

Several big changes concerning updates since 2022.

• Namely, replacement of --partition={serial,parallel} by the equivalent --qos, but with significant changes on the relevant text.
• Updates on timeline graphs and so on (done with odg -> ods -> pdf, even though a better alternative exists elsewhere (?)
• Removed --reservation on the examples. Since the course now runs on Helvetios we don't need this.
• Added a pdfpc file (for use with the equally name pdf presenter on Linux) with comments along the slides.