Upload error improvement and bug fixes

Fix update partition size in [ESP420]
add upload file size checking
better upload error management
use grbl version + build version for better tracking
new embedded page from 3.0
   - display fw version
   - menu link link to wiki / github
   - auto detection of index.html.gz when uploaded
   - websocket to limit to one instance
   - build batch to generate page and fw file
fix for Apple captive portal blocking websocket
Change `Error 0` message to `No connection`

embedded/header.txt

@@ -0,0 +1,24 @@
+/*
+  nofile.h - ESP3D data file
+
+  Copyright (c) 2014 Luc Lebosse. All rights reserved.
+
+  This library is free software; you can redistribute it and/or
+  modify it under the terms of the GNU Lesser General Public
+  License as published by the Free Software Foundation; either
+  version 2.1 of the License, or (at your option) any later version.
+
+  This library is distributed in the hope that it will be useful,
+  but WITHOUT ANY WARRANTY; without even the implied warranty of
+  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+  Lesser General Public License for more details.
+
+  You should have received a copy of the GNU Lesser General Public
+  License along with this library; if not, write to the Free Software
+  Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
+*/
+
+//data generated by https://github.com/AraHaan/bin2c
+//bin2c Conversion Tool v0.14.0 - Windows - [FINAL].
+#ifndef __nofile_h
+#define __nofile_h