Productive Scale needs some Enhancements

[Micah]

One issue with the fort idea is that it's dominion dependent, so high-production nations with low dominion scores could have to go to a good deal of trouble to get their dominion in place to build an expansion fort, while bless-nations can avoid the sloth penalty the same way. Only Awe-based SCs with sloth are likely to feel the effects of the change, since they tend to have a ton of dominion spread. It would be nice for production to matter more beyond the first 10 turns though.