moved to logic from api to lib

Models/CropYieldModel.cs

@@ -0,0 +1,24 @@
+using System;
+using System.Collections.Generic;
+using System.Text;
+
+namespace FarmMapsAPI.Carbon.Models
+{
+    public class YearData
+    {
+        public int Year { get; set; }
+        public double YieldValue { get; set; }
+    }
+
+    public class Yield
+    {
+        public string ProvinceCode { get; set; }
+        public List<YearData> YearData { get; set; }
+    }
+
+    public class CropYieldModel
+    {
+        public string CropName { get; set; }
+        public List<Yield> Yields { get; set; }
+    }
+}