Add last extension property from UnshieldSharp

SabreTools.Serialization/Wrappers/InstallShieldCabinet.cs

@@ -15,6 +15,12 @@ namespace SabreTools.Serialization.Wrappers
 
         #region Extension Properties
 
+        /// <summary>
+        /// Reference to the next cabinet header
+        /// </summary>
+        /// <remarks>Only used in multi-file</remarks>
+        public InstallShieldCabinet? Next { get; set; }
+
         /// <summary>
         /// Number of components in the cabinet set
         /// </summary>