Merge pull request #648 from jonathanantoine/feature/more-details-in-exceptions

Add error code in exception message of InAppBillingPurchaseException.

Author: jamesmontemagno

src/Plugin.InAppBilling/Shared/InAppBillingExceptions.shared.cs

@@ -90,12 +90,12 @@ public class InAppBillingPurchaseException : Exception
         /// </summary>
         /// <param name="error"></param>
         /// <param name="ex"></param>
-        public InAppBillingPurchaseException(PurchaseError error, Exception ex) : base("Unable to process purchase.", ex) => PurchaseError = error;
+        public InAppBillingPurchaseException(PurchaseError error, Exception ex) : base($"Unable to process purchase : {error:G}.", ex) => PurchaseError = error;
         /// <summary>
         /// 
         /// </summary>
         /// <param name="error"></param>
-        public InAppBillingPurchaseException(PurchaseError error) : base("Unable to process purchase.") => PurchaseError = error;
+        public InAppBillingPurchaseException(PurchaseError error) : base($"Unable to process purchase : {error:G}.") => PurchaseError = error;
 
         /// <summary>
         ///