Addreversedsuits

This PR adds the mechanisms for Reversed suits, and adds the simplest Reversed variants (3-6 suits).
This is the first step to enable the Black Powder official variant (i.e. White Reversed) and other derivatives.
Also refactor the "Up and Down" variant code to reduce comparing with copies of the variant name, and reuse code between "Up and Down" and any "Reversed" variants.

TODO: better icons/visual treatment when playing with Reversed suits.

该提问来源于开源项目：Zamiell/hanabi-live