AI disapproves intercultural customs union
Thumbnail self-explanatory.
Added two AI acceptance modifiers to customs union:
1. "-100" acceptance score if AI country’s citizenship law discriminates against all of your primary cultures
2. "-100" acceptance score if none of AI country’s primary culture shares a non-heritage trait with your country
In other words, we will not see Russo-Turkish or Russo-Chinese customs union. British-Belgian customs union is also virtually impossible to happen since their culture is not similar (i.e. no common non-heritage trait).
Compatibility:
This will override a vanilla file in "diplomatic_actions" folder so any mod modifying it (such as VTM) will not be compatible, although it will not be game-breaking neither.
