docs: Improve documentation

[chrispap95]

Let's improve the documentation and close the open issues.

Changelog:

• I improved the algorithm description section. I used LaTeX for the formulas and added all the missing distance measures.
• I updated links to point to the official documentation of v3.4.1 instead of v3.4.0.
• I made the invariant masses of the particles positive by increasing their energies. Still, we might want to put something more realistic there in the future.
• The role of registering the behavior using vector and using with_name="Momentum4D" is emphasized (and hopefully clearer).