Resource Priorities

Add a resource priority to both buildings that need
them to produce their wares, and to building sites.

Something like this:
Building site Priority:
1: Low priority, buildingsite only gets resources when
there aren't any 2 or 3 sites requiring it.
2: Normal priority, buildingsite gets resources as normal
3: High priority, buildingsite gets resources before
any 1 or 2 sites.

With producing buildings:
1: Low priority: Site only gets resources when there
aren't any build-sites requiring it, or level 3
production sites.
2: Normal priority: Resources are shared as normal
3: This building takes all available resources not
needed for level 3 building sites, and over any level 1
or 2 sites.

The way these two modes interact to split materials
between either level 2 builders or level 2 producers
should perhaps be discussed, maybe an option to set
building sites as more important than production sites
or the other way around is needed as well.

The reason for this request is that it is so stupid
that even when you have a major shortage of wood, and
there are 3 lumberjacks waiting for construction, most
of the wood is still transported to a wood hardener,
even though there is no current need for it's product.
Or, when short on axes, it finishes a lumberjack in the
east, and a ranger in the west, so the lumberjack
doesn't do anything and the ranger builds a forest,
even though there were 2 lumberjacks waiting for
construction. I think this control of where the raw
materials go is very important, because right now it
really causes very long and annoying waits, because all
the wood is distributed wrong, for instance.