Fix missing main div in example file system
@@ -59,6 +59,7 @@ responseData[] = ""
" <div class=\"container\">\n"
" <h1>Welcome to web server hosted by ESP8266 Wi-Fi module!</h1>\n"
" </div>\n"
+ " <div id=\"maindiv\"></div>"
" <footer>\n"
" <div class=\"container\">\n"
" Copyright &copy; 2017. All rights reserved. Webserver is hosted on ESP8266.\n"
