This update improves the visualization of burning cities and allows saving most visualization settings.

Burning cities

- New Feature: burning cities are animated, the size of the displayed burning area is displaying the area affected by 10 cal/cm^2
- New Feature: smoke from burning cities is moving with the speed of the wind
- New Feature: smoke from burning cities scales with the amount of burning fuel

Visualization settings

- New Feature: graphics settings are saved 

- New Feature: city lights intensity can be adjusted 

- New Feature: minimum displayed harbor size can be set and saved 

- Bug Fix: temperature went to zero if soot amount went over 150 Tg