Automatic trading statistics are here!

Bug fixes:
* there were still scenarios where you could end up with perpetual winter :(
* in the main menu, people could walk outside the roads
* deleting a ship from a convoy could incorrectly change the leader of the convoy
* the quest history could show up empty

Changes & new features:

* there is now an interface to see what, where, and how much your convoys have traded!

* ports can no longer freeze in the Tutorial
* adaptive consumption is now no longer used in the calculation of prices (prices won't jump lower after you buy some goods)
* Timberyard recipe no longer requires logs
* added 4 new difficulty levels! I've postponed the last and whackiest of them all (needs more time)
* ai traders now have a small preferences towards returning to their home town. Also changed where they spawn to be more balance
* re-ordered monthly input goods & build cost goods to ensure they're alphabetical