Make model type inherent to interface

SabreTools.Serialization/Interfaces/IWrapper.cs

@@ -1,11 +1,20 @@
 namespace SabreTools.Serialization.Interfaces
 {
-    public interface IWrapper
+    /// <summary>
+    /// Represents a wrapper around a top-level model
+    /// </summary>
+    /// <typeparam name="TModel">Top-level model for the wrapper</typeparam>
+    public interface IWrapper<TModel>
     {
         /// <summary>
         /// Get a human-readable description of the wrapper
         /// </summary>
         string Description();
+
+        /// <summary>
+        /// Get the backing model
+        /// </summary>
+        TModel GetModel();
         
 #if !NETFRAMEWORK
         /// <summary>

SabreTools.Serialization/Wrappers/WrapperBase.cs

@@ -8,7 +8,7 @@ using SabreTools.Serialization.Interfaces;
 
 namespace SabreTools.Serialization.Wrappers
 {
-    public abstract class WrapperBase<T> : IWrapper
+    public abstract class WrapperBase<T> : IWrapper<T>
     {
         #region Descriptive Properties
 
@@ -24,6 +24,9 @@ namespace SabreTools.Serialization.Wrappers
 
         #region Properties
 
+        /// <inheritdoc/>
+        public T GetModel() => Model;
+
         /// <summary>
         /// Internal model
         /// </summary>