Only expand settlement range for certain buildings

Current set of buildings affecting range: Warehouse, Storage tent, Lookout.
Lookout range has been drastically lowered to account for this new role.
It now has the same range as tents do, half of what a storage tent does (approximately) and a quarter of its old range.

While (surprisingly enough) this change is apparently all that's needed, and it is stable across save-load as well, AI code probably needs to be looked at and adapted.

Reasons for the change (not an exhaustive reasoning by any means):
The reason why all buildings expanded range up until now was pretty much coders writing code to support a concept of "settlement range", but then game design not happening to define what that should entail or how it would look in practice.
"Not happening" to the degree of not even a DD wiki page being written despite red link from our main DD. In years. So let's just do something.

I believe having to manage (in some way) your available land area is interesting, and this does allow for several potentially interesting related changes as well, the most prominent of which probably is introducing running costs for storage tent and lookout.

Big fat note: Removing buildings from now on is supposed to *reduce* settlement range as well! Else we just continue rewarding degenerated tactics like building lookouts all across the island, then tearing them down again after the matter to save on running costs.

Open tasks:
- [x] Handle removal of range-affecting buildings (decrease settlement range accordingly)
- [x] Display running costs of lookout in overview tab (not sure this would be good for warehouse, storage tent)