Decisions to expel non-accepted POP

[SimonWeber]

Due to my comment in #128 the idea to expel non-accepted POP and replace them with the primary culture POP or the nearest accepted culture POP could be implemented in general for each country. From my games I know there is an event that sometimes pops up to push the promotion of the core territory. It is rather rare and if it triggers it works very slow.
Can there be an additional decision that pushes it even further?

Let's talk about such a decision could be designed.
Will it cost infamy and money?
Does it just appear in the decision list if a new region is conquered?
How can the non-accepted be replaced with the primary without getting an empty state?
The destination of the expelled POP should be rather a country where they are accepted or primary culture, is that possible to implement?
To prevent a weird culture mapmode border gore the nearest accepted culture should move into the conquered land.

Saludos and thanks for the great mod!