refactor interfaces

[3k-dome]

Most of the implementations in Road or Settlement, and so on, could be moved into their interfaces as default implementations. Derived classes that need to change those may then override or extend them.

Observable variants of those classes could then call the default method and simply send update notifications on properties that don't send them automatically. For example, an obserable Player class would only need to send property changed events after any resource changes since dictionaries are not observable.

[3k-dome]

The whole Catan definition thing is really annoying.

public IEnumerable<float> ToVector<TSettlement, TRoad, TDice>(Catan<TSettlement, TRoad, TDice> catan)
    where TSettlement : ISettlement, new()
    where TRoad : IRoad, new()
    where TDice : IDice, new();

[3k-dome]