Improve frontend and add "How to use" (#3)

index.php

@@ -46,7 +46,7 @@
         // Informations for user
         if ($_SERVER['REQUEST_METHOD'] === 'GET')
         {
-                if (stristr($_SERVER["HTTP_USER_AGENT"], 'curl'))
+                if (stristr($_SERVER["HTTP_USER_AGENT"], 'curl') or stristr($_SERVER["HTTP_USER_AGENT"], 'Wget'))
                 {
                         print("To upload file, use # curl --upload-file my_file " . _HTTP_PROTO . '://' . _HTTP_DOMAIN . _HTTP_PATH . "index.php\n");
                 }