+ auto-update: copy supporting files (README, etc.)

AGHTechDoc.md

@@ -217,10 +217,13 @@ Algorithm of an update by command:
 	* Copy the current configuration file to the directory we unpacked new AGH to
 	* Check configuration compatibility by executing `./AGH --check-config`.  If this command fails, we won't be able to update.
 	* Create `backup-vXXX` directory and copy the current configuration file there
-	* Stop all tasks, including DNS server, DHCP server, HTTP server
+	* Copy supporting files (README, LICENSE, etc.) to backup directory
+	* Copy supporting files from the update directory to the current directory
 	* Move the current binary file to backup directory
 	* Note: if power fails here, AGH won't be able to start at system boot.  Administrator has to fix it manually
 	* Move new binary file to the current directory
+	* Send response to UI
+	* Stop all tasks, including DNS server, DHCP server, HTTP server
 	* If AGH is running as a service, use service control functionality to restart
 	* If AGH is not running as a service, use the current process arguments to start a new process
 	* Exit process