Added "in this city", "in other cities" conditionals for city-based uniques

More UI cleanup

Removed many double / badly-placed icons

Tileset no longer reverts on Android after restarting game

Solved randomness issues with Retreat chance and unit gain from defeat

By SomeTroglodyte:
- Unhappiness effects
- Fix more leaks of the actual Player count in random mode
- Allow city & tile conditionals on production-to-stat-enabling unique

Make new "Charts" button translatable  - By Ouaz