Rail depots, mines and oilfields now provide supply level 1 if isolated from cities or capitals.
On screen you can see that Mine has supply 4, it is cut off from capital and even from any city. Here, supply should be 1. This is bug or something I do not understand?

At sea, supply has always 5. Why in ports of island supply 3? Supply in port should be not worse than in sea, even if it is island-port for Naval Units.
