Init LicenseUtils ctor when JsConfig is first used.

Author: mythz

src/ServiceStack.Text/JsConfig.cs

@@ -18,6 +18,7 @@ static JsConfig()
             //JsConfig<System.Drawing.Color>.SerializeFn = c => c.ToString().Replace("Color ", "").Replace("[", "").Replace("]", "");
             //JsConfig<System.Drawing.Color>.DeSerializeFn = System.Drawing.Color.FromName;
             Reset();
+            LicenseUtils.Init();
         }
 
         public static JsConfigScope BeginScope()

src/ServiceStack.Text/LicenseUtils.cs

@@ -111,6 +111,12 @@ static LicenseUtils()
             PclExport.Instance.RegisterLicenseFromConfig();
         }
 
+        private static bool hasInit;
+        public static void Init()
+        {
+            hasInit = true; //Dummy method to init static constructor
+        }
+
         public static class ErrorMessages
         {
             private const string UpgradeInstructions = " Please see https://servicestack.net to upgrade to a commercial license or visit https://github.com/ServiceStackV3/ServiceStackV3 to revert back to the free ServiceStack v3.";