YAML overhaul

[465b]

I currently dislike some choices present in the YAML config file.

• only the secondly named compartment must and can be named as interaction parameter.
  this choice seems arbitrary and makes the existence of "inverse interactions" necessary,
  which is a confusing concept imo
• inconsistency in the titles.
  • "compartment" without plural s
  • "interactions" with plural s
• case sensitivity in the title?
• "optimize" flag needs to be present in compartments which shouldnt be the case anymore