Replace initNationalities passage with JS, and remove hardcoded nationality sets from it (use the vanilla presets instead).

1. Remove albinism stuff from getHeroSlave and just let deepAssign handle the albinism override.
2. Make deepAssign handle null values better, so it doesn't puke over the albinism override.
3. Refactor hero slave cost calculation to a separate function instead of repeating the same inscrutable logic multiple places.

This reverts merge request !5896

many fixes

tabs

fix