Shipyards from Frontier

[VMSolidus]

Description

I don't have a lot to say on this, other than that this feature needs to be ported after Frontier Economy is ported. Frontier has an excellent implementation of Shipyards, something we will want to have in this code base. The only real changes we wish to make sure it has are related to the changes needed for Economy. Shipyards need to be configurable if they use station funding, vs. personal funding.