Fixes for Phylla and Urta

This bug was caused by the code for fixing up old save files. It incorrectly saw any file where Urta was pregnant as a file where she was pregnant with eggs.

I've fixed this in two ways: first by detecting for proof that this is actually a new save and not modding the values. This method isn't entirely foolproof (though it should work for most cases), so I've also added an integer file version in one of the flags. I wasn't sure how far I could trust the existing save version string.

Anyway, any file that has the new file version will be treated correctly. Also any file from prior to the pregnancy system update will work properly. As for the saves created in between - the vast majority will work properly.