feat: Add .remove method to deck class (#681)

[RaphaelHeiniger]

Usage:

mydeck = Deck()
mydeck.extend([some keywords])
mydeck.remove(i) or mydeck.remove([i, j, k])

[koubaa]

Could you please include a test?

[RaphaelHeiniger]

Good point, sure I will add one.

[RaphaelHeiniger]

@koubaa I just figured that one can do now deck.remove(...) but on the individual lists e.g. deck.keywords.remove(...) or deck.string_keywords.remove(...) obviously still does not work. Do you think it makes sense to add this functionality as well there or is there already another intended way to to this?

[koubaa]

@RaphaelHeiniger those aren't lists in themselves, those are just filters applied on the main list. I think what you have done in this PR is probably the best we can do.