Add XML docs to core packages

src/Microsoft.AspNetCore.SpaServices/Prerendering/JavaScriptModuleExport.cs

@@ -1,14 +1,36 @@
+using System;
+
 namespace Microsoft.AspNetCore.SpaServices.Prerendering
 {
+    /// <summary>
+    /// Describes how to find the JavaScript code that performs prerendering.
+    /// </summary>
     public class JavaScriptModuleExport
     {
+        /// <summary>
+        /// Creates a new instance of <see cref="JavaScriptModuleExport"/>.
+        /// </summary>
+        /// <param name="moduleName">The path to the JavaScript module containing prerendering code.</param>
         public JavaScriptModuleExport(string moduleName)
         {
             ModuleName = moduleName;
         }
 
+        /// <summary>
+        /// Specifies the path to the JavaScript module containing prerendering code.
+        /// </summary>
         public string ModuleName { get; private set; }
+
+        /// <summary>
+        /// If set, specifies the name of the CommonJS export that is the prerendering function to execute.
+        /// If not set, the JavaScript module's default CommonJS export must itself be the prerendering function.
+        /// </summary>
         public string ExportName { get; set; }
+
+        /// <summary>
+        /// Obsolete. Do not use. Instead, configure Webpack to build a Node.js-compatible bundle and reference that directly.
+        /// </summary>
+        [Obsolete("Do not use. This feature will be removed. Instead, configure Webpack to build a Node.js-compatible bundle and reference that directly.")]
         public string WebpackConfig { get; set; }
     }
 }