More variation in cities based on population and planet size, from Paragon.
Change to using the population instead of radius.
Up the minimum and no-atmosphere maximum limit.
Merge pull request #3227 from fluffyfreak/CityVariety

More variation in city size / dimension.
Update Changelog.txt
Merge pull request #3236 from fluffyfreak/deadzone

Deadzone
Update Changelog.txt
Merge branch 'master' of https://github.com/pioneerspacesim/pioneer into analogue-thrust