feat: move PD Core into Essentials

src/PepperDash.Core/XSigUtility/Serialization/XSigSerializationException.cs

@@ -0,0 +1,28 @@
+using System;
+
+namespace PepperDash.Core.Intersystem.Serialization
+{
+    /// <summary>
+    /// Class to handle this specific exception type
+    /// </summary>
+    public class XSigSerializationException : Exception
+    {
+        /// <summary>
+        /// default constructor
+        /// </summary>
+        public XSigSerializationException() { }
+
+        /// <summary>
+        /// constructor with message
+        /// </summary>
+        /// <param name="message"></param>
+        public XSigSerializationException(string message) : base(message) { }
+
+        /// <summary>
+        /// constructor with message and innner exception
+        /// </summary>
+        /// <param name="message"></param>
+        /// <param name="inner"></param>
+        public XSigSerializationException(string message, Exception inner) : base(message, inner) { }
+    }
+}