Add 2019 Merchants of the seas expansion

[driesdeproost]

https://images.zmangames.com/filer_public/17/3b/173b2f1b-c493-409b-8927-fc36a6cacd64/zm7244_rulebook_en.pdf

I might give implementing this a try, but I'll have to read into the project quite a bit first

[lvandeve]

Neat! I'll gladly accept a patch if you manage to implement it

It might be somewhat challenging because a lot of code is hardcoded for the original version. I managed to generalize things for the fire ice expansion and then contain the implementation of that expansion itself in fireice.js, but merchants of the seas will need its own different generalizations