[Modify] Rename it

Example3/App.config

@@ -2,7 +2,7 @@
 <configuration>
   <appSettings>
     <add key="CertFilePassword" value="password"/>
-    <add key="RootPath" value="../../Public"/>
+    <add key="DocumentRootPath" value="../../Public"/>
     <add key="ServerCertFile" value="/path/to/cert.pfx"/>
   </appSettings>
 </configuration>

Example3/Program.cs

@@ -82,7 +82,7 @@ namespace Example3
       //httpsv.ReuseAddress = true;
 
       // Set the document root path.
-      httpsv.RootPath = ConfigurationManager.AppSettings["RootPath"];
+      httpsv.DocumentRootPath = ConfigurationManager.AppSettings["DocumentRootPath"];
 
       // Set the HTTP GET request event.
       httpsv.OnGet += (sender, e) => {