scrolling weatherbox; new skybox clut

assets/mods/basegame/weathers/WeatherGeneric.json

@@ -18,5 +18,6 @@
       "baseScale": 1.0, "scaleVariance": 0.6,
       "altLow": 80, "altHigh": 800
     }
-  }
+  },
+  "atmoTurbidity": 3.5
 }

assets/mods/basegame/weathers/WeatherGeneric2.json

@@ -24,5 +24,6 @@
       "altLow": 1600, "altHigh": 2400
     }
   },
+  "atmoTurbidity": 3.5,
   "__comment__": "Make a texture for altocumulus so that this weather can be realised with less than 1000 sprites"
 }

assets/mods/basegame/weathers/WeatherOvercast.json

@@ -6,7 +6,7 @@
   "cloudGamma": [2.2, 2.0],
   "cloudGammaVariance": [0.1, 0.1],
   "windSpeed": 10.45,
-  "windSpeedVariance": 1.0,
+  "windSpeedVariance": 0.5,
   "clouds": {
     "cumulus": {
       "filename": "cloud_normal.png", "tw": 1024, "th": 512, "probability": 0.1,
@@ -23,5 +23,6 @@
       "baseScale": 4.0, "scaleVariance": 0.1,
       "altLow": 100, "altHigh": 100
     }
-  }
+  },
+  "atmoTurbidity": 9.5
 }