Comment 8 for bug 1170086

Reading #6 again I see you were talking about return values. If they are put in the conf file, which I'm not against, this does not solve the issue with returned ware of enhanced buildings vs directly built ones. So we must allow two values in that section as well.

I think of keeping a pointer (or vector of pointer) to the Descr of the former building if enhanced - this is already done in constructionsite. This way we can easily track down the return values for all enhancement steps.