Added a Gene for Gender Fluid Pawns

Source/Genes/Gender/Defs/GenderFluidExtension.cs

@@ -0,0 +1,20 @@
+using Verse;
+
+namespace RJW_Genes
+{
+    public class GenderFluidExtension : DefModExtension
+    {
+        /// <summary>
+        /// Number of ticks until the change can be triggered.
+        /// Just being "triggered" does not mean changing, see the changeChance below. 
+        /// </summary>
+        public int changeInterval;
+
+        /// <summary>
+        /// How high is the chance to change gender?
+        /// Set to 1 for "always", set to 0 for "never". 
+        /// Everything else is a bit statistics, but e.g. when set to .5 the chances grow per day from [50%, 75%, 82.25%, ...]
+        /// </summary>
+        public float changeChance;
+    }
+}