Adds massive cargo ships to the game, that function similarly to trains. Also adds deep sea oil, oil platforms, tanker ships, train bridges and other water based content.
Currently all boats and water ways have the same selection_priority of 50. You should increase that of all boats to 51, or decrease the water ways' to 49 so that you can always select the boat over the water way (then it would behave the same as trains vs tracks). https://wiki.factorio.com/Prototype/Entity#selection_priority
