Added generic DefModExtension for Distance and Ticks

Source/Common/Defs/DistanceExtension.cs

@@ -0,0 +1,20 @@
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Text;
+using System.Threading.Tasks;
+using Verse;
+
+namespace RJW_Genes
+{
+
+    /// <summary>
+    /// Small Extension that covers distances for Genes.
+    /// This allows to set distance in the XMLs. 
+    /// The distance is measured in tiles, so a distance of ~25 means 25 tiles away from the pawn in any direction. 
+    /// </summary>
+    public class DistanceExtension : DefModExtension
+    {
+        public int Distance;
+    }
+}