Reconsider changing isPositiveInteger to isIntegerValue for AIC values that permit cheating

[gynt]

@Krarilotus

[gynt]

The question is, should people be able to cheat?

Solution: warning for invalid values, no errors.

Logic:

1. Validate for impossible values, throw fatal errors
2. Warn for cheat values (negative integers), place warnings in the logs (or popups on preference?)
3. Set the value

[Krarilotus]

For now, i would say we should mimic the behaviour of the old UCP as close as possible, that way people just get what they expect, and add all the fancy shenanigans on top later. -> Hence i would suggest switching all checks for positive integers to normal integers for now, until we have a proper way of handling this, so AIs work as expected!

[gynt]

Partly done in the PR (#14) for fields that haven relevant negative values.