Enforce the assumption that one unique settings file should lead to one unique problem name and RamAirKite

[1-Bart-1]

• use get_prob_name(set) at the start of creating the RamAirKite
• add a field prob_name to the RamAirKite and make this field immutable by overriding Base.setproperty!
• check in reinit! if the prob_name has changed and throw an error if it has changed

[ufechner7]

Can't you make it immutable by defining it const?

[1-Bart-1]

Replaced by #217