buildsys: keep d/copyright file statically included

This doesn't change often (not sure if sencha even will make another
GPL release..) and if installed dynamically on build from the extjs
license.txt it also is incomplete w.r.t. our packaging copyright.

Just copy the content of extjs/licenses/license.txt over once into
debian/copyright.

Signed-off-by: Thomas Lamprecht <t.lamprecht@proxmox.com>

Makefile

@@ -14,7 +14,6 @@ $(BUILDDIR): debian extjs
 	rm -rf $@ $@.tmp && mkdir -p $@.tmp/extjs
 	cp -a debian/ $@.tmp/debian
 	cp -a extjs/build/ $@.tmp/extjs/build
-	cp extjs/licenses/license.txt $@.tmp/debian/copyright
 	mv $@.tmp $@
 
 .PHONY: deb

debian/copyright

@@ -0,0 +1,77 @@
+Top-level debian/ & Makefile packaging und build-sys;
+
+ Copyright (C) 2017 - 2023 Proxmox Server Solutions GmbH
+ License: AGPL-3.0-or-later
+
+For the ExtJS JavaScript Framework (GPLv3 variant) the following was copied in
+verbatim form the projects license.txt:
+
+Ext JS 7.0.0.168 - JavaScript Library
+Copyright (c) 2006-2020, Sencha Inc.
+All rights reserved.
+licensing@sencha.com
+
+http://www.sencha.com/license
+
+Open Source License
+------------------------------------------------------------------------------------------
+This version of Ext JS 7.0.0.168 is licensed under the terms of the Open Source GPL 3.0 license. 
+
+http://www.gnu.org/licenses/gpl.html
+
+
+Alternate Licensing
+------------------------------------------------------------------------------------------
+Commercial and OEM Licenses are available for an alternate download of Ext JS 7.0.0.168.
+This is the appropriate option if you are creating proprietary applications and you are 
+not prepared to distribute and share the source code of your application under the 
+GPL v3 license. Please visit http://www.sencha.com/license for more details.
+
+
+Third Party Content
+------------------------------------------------------------------------------------------
+The following third party software is distributed with Ext JS 7.0.0.168 and is 
+provided under other licenses and/or has source available from other locations. 
+
+Library: YUI 0.6 (BSD Licensed) for drag-and-drop code.
+Location:<3A>http://developer.yahoo.com/yui
+License:<3A>http://developer.yahoo.com/yui/license.html (BSD 3-Clause License)
+
+Library: JSON parser
+Location: http://www.JSON.org/js.html
+License: http://www.json.org/license.html (MIT License)
+
+Library: flexible-js-formatting 
+Location:<3A>http://code.google.com/p/flexible-js-formatting/
+License:<3A>http://www.opensource.org/licenses/mit-license.php (MIT License)
+
+Library: sparkline.js 
+Location: http://omnipotent.net/jquery.sparkline
+License:  http://omnipotent.net/jquery.sparkline  (BSD 3-Clause License)
+
+Library: DeftJS 
+Location: http://deftjs.org/
+License: http://www.opensource.org/licenses/mit-license.php (MIT License)
+
+Library: Open-Sans
+Location: http://www.fontsquirrel.com/fonts/open-sans
+License: http://www.fontsquirrel.com/fonts/open-sans (Apache 2.0 License)
+
+Ext JS 7.0.0.168 Examples:
+
+Library: Silk Icons 
+Location: http://www.famfamfam.com/lab/icons/silk/
+License: http://www.famfamfam.com/lab/icons/silk/ (Creative Commons Attribution 2.5 License)
+
+Library: Font Awesome CSS
+Location: http://fontawesome.io/
+License: http://fontawesome.io/3.2.1/license/ (MIT)
+
+Library: Material Design Icons
+Location: https://github.com/google/material-design-icons
+License: https://github.com/google/material-design-icons/blob/master/LICENSE (Apache)
+
+
+--
+
+THIS SOFTWARE IS DISTRIBUTED "AS-IS" WITHOUT ANY WARRANTIES, CONDITIONS AND REPRESENTATIONS WHETHER EXPRESS OR IMPLIED, INCLUDING WITHOUT LIMITATION THE IMPLIED WARRANTIES AND CONDITIONS OF MERCHANTABILITY, MERCHANTABLE QUALITY, FITNESS FOR A PARTICULAR PURPOSE, DURABILITY, NON-INFRINGEMENT, PERFORMANCE AND THOSE ARISING BY STATUTE OR FROM CUSTOM OR USAGE OF TRADE OR COURSE OF DEALING.