Default with Every Subset

[dwarftough]

Implementing my old idea. This is the same as the Default/Age of Heroes era but with random options for every non-empty subset of factions. If you wished to play 'Any faction but X' or 'X or Y or Z randomly', this will save you from restarting games if a wrong faction rolls.

Version 1.0.0 just released as it is, potential improvements: different icons for different Random options instead of dice (for example, No Drakes can be a dice and a drake crossed with a red cross)