remove LinGui dialog blocking (no need anymore), revert changes in collecting garbage after window close, new design for save dialog, add license and copyright links and cleanup new modules, add OberonCore to About and License, change text in Scratch

BlackBox/LICENSE.txt

@@ -1,4 +1,7 @@
+BSD 2-Clause License
+
 Copyright (c) 2017 - 2021 Alexander V. Shiryaev, Ivan A. Denisov, Igor A. Dehtyarenko, Anton A. Dmitriev
+Copyright (c) 2013 - 2021 OberonCore
 Copyright (c) 2013 - 2019 BlackBox Framework Center
 Copyright (c) 1994 - 2013 Oberon microsystems, Inc., Switzerland. All rights reserved.