Generate weather conditions at turn start.

Weather and exact time of day information is helpful during mission
planning, so generate it at the start of the turn rather than at
takeoff time.

Another advantage aside from planning is that we can now use the wind
information to set carrier headings and takeoff runways appropriately.

qt_ui/widgets/QTopPanel.py

@@ -97,7 +97,7 @@ class QTopPanel(QFrame):
         if game is None:
             return
 
-        self.turnCounter.setCurrentTurn(game.turn, game.current_day)
+        self.turnCounter.setCurrentTurn(game.turn, game.conditions)
         self.budgetBox.setGame(game)
         self.factionsInfos.setGame(game)