[Exploit] Destroying cities

[Xilmi]

If you conquer a city and it's pop-growths is less than -1 then setting the city to selfdestruct can significantly slow down the loss in population.

For example: A freshly conqured size 27 city has -4 pop-growth per turn usually. Until it recovers you lose about 20 pop.
If you set it to selfdestruct instead you only lose 1 pop per turn. And when it recovers you may have lost only about 8 pop.

So if both: Self-destruct and negative growth are active at the same time the one that is more effective shall count. Or they should be added together.

[Xilmi]

Halfing migration moves the amount of population where the exploit becomes effective. It doesn't solve the inheritent problem!
The solution would be adding migration and raze-effect if both it active at the same time.

Here's 2 more screenshots:

1. Takeover migration:

2. Pop-loss due to raze:

The latter is way lower. And it saves a lot of food on top of that.