better ship variety at select ports

[yowshi]

it's way too hard to find some ships in the various markets.

so I thought maybe expand the ships you can buy from factories and shipyards to include any ships from a faction not hostile with that base's faction.

alternatively, some kind of search feature in a bases info section to help players find where the ship they are looking for is being sold.

[BenjamenMeyer]

An interesting idea. Certainly worth looking into once we can get someone doing more work on the assets.