Add domain exception handling for authorization and data conflicts

EnvelopeGenerator.Domain/Exceptions/AuthorizationException.cs

@@ -0,0 +1,17 @@
+#if NETFRAMEWORK
+using System;
+#endif
+
+namespace EnvelopeGenerator.Domain.Exceptions
+{
+    public class AuthorizationException : Exception
+    {
+        public AuthorizationException(string message) : base(message)
+        {
+        }
+
+        public AuthorizationException()
+        {
+        }
+    }
+}

EnvelopeGenerator.Domain/Exceptions/DataIntegrityException.cs

@@ -9,5 +9,9 @@ namespace EnvelopeGenerator.Domain.Exceptions
         public DataIntegrityException(string message) : base(message)
         {
         }
+
+        public DataIntegrityException() : base()
+        {
+        }
     }
 }