Unified Ball Filtering/Team ball

[MegaIng]

Summary

Especially with #925 merge, the robots need to have a proper agreement on where the ball is. The current solution is suboptimal in e.g. the presence of unlocalized robots.

[jaagut]

@MegaIng what do you mean/want to achieve with "unified"?

[MegaIng]

I think I used unified to mean the same behavior on all robots and a central place on each robot that makes the decision, but unified isn't the correct term for that.