Supporting lazy sequences

[StrykerKKD]

Lazy sequences make it possible to support negation in infinite domains, where the Set solution is not viable. Lazy sequences is also a good choice, because they are made by generators, which mean that a generator could implement a costume search strategy for the specified domain.

It should be implemented with Base.Sequence, because it's already used in the codebase. Implementing this could be challenging due to the lazyness.