feat: disable pollution in cost calculations

Most Pyanodons' users play without pollution. If they do play with pollution, then they likely use other apps to figure out which recipe to use.

Closes #111

Yafc.Model/Analysis/CostAnalysis.cs

@@ -19,7 +19,7 @@ public static CostAnalysis Get(bool atCurrentMilestones) {
         private const float CostPerProductPerSize = 0.2f;
         private const float CostPerItem = 0.02f;
         private const float CostPerFluid = 0.0005f;
-        private const float CostPerPollution = 0.01f;
+        private const float CostPerPollution = 0;
         private const float CostLowerLimit = -10f;
         private const float CostLimitWhenGeneratesOnMap = 1e4f;
         private const float MiningPenalty = 1f; // Penalty for any mining