AI moves civilians off capital to make way for spaceship parts

AI considers capital city strength when deciding to declare war

By vegeta1k95:
- Big rework of City buttons
- Fix PolicyScreen for odd-numbered branches
- Better tech buttons

By CrispyXYZ:
- Fixed removing improvements in map editor

Solved 'tiles still belonging to razed cities' - By nacro711072

Negative stats UI Updates - By itanasi

Add setting to disable easter eggs. - By FiretronP75