Update to GPL3 License, clarify AUTHORS

AUTHORS

@@ -7,57 +7,96 @@ It still holds many of the symlinks that upstream elementary dropped.
 
 These icons are free artwork; you can redistribute them and/or modify
 them under the terms of the GNU General Public License as published by
-the Free Software Foundation; either version 2, or (at your option)
+the Free Software Foundation; either version 3, or (at your option)
 any later version.
 
-These icons distributed in the hope that it will be useful,
+This icon set 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 General Public License for more details.
 
 You should have received a copy of the GNU General Public License
-along with these icons; if not, see <http://www.gnu.org/licenses/>.
+along with these icons; if not, see <https://www.gnu.org/licenses/>.
 
-GNOME icons, Humanity icons, and elementary icons are all licensed
-under the GPL.
+------------------------------------------------------------------
+------------------------------------------------------------------
 
-Icons based on GNOME and other GNOME projects are licensed GPL.
-You can visit the GNOME website here: https://www.gnome.org
+While this package and icon set is GPL-3.0 licensed, additional elements
+were used from sources with other, GPL-3.0-compatible, licenses. The full
+text of these licenses can be found in the /licenses folder. The authors,
+licenses, links, and files which use additional elements are listed below.
 
-Icons based on Tango sources or taken from the Tango project are public domain.
-You can visit the Tango project website here:
-http://tango.freedesktop.org/Tango_Desktop_Project
 
-Icons based on Humanity sources or taken from the elementary project are licensed GPL.
-You can visit the Humanity website here: https://launchpad.net/humanity
+=== Apache 2.0 ===
 
-Kotlin logo licensed under Apache License 2.0 by JetBrains
-https://kotlinlang.org/docs/kotlin-logo.html
+Crystal logo licensed under the Apache License, Version 2.0.
+Copyright © 2012 Manas Technology Solutions
+Files: text-x-crystal
+https://crystal-lang.org/media/
+https://www.apache.org/licenses/LICENSE-2.0
+
+Kotlin™ logo licensed under Apache License 2.0 by JetBrains
+Files: text-x-kotlin
+https://kotlinlang.org/docs/kotlin-brand-assets.html
 http://www.apache.org/licenses/LICENSE-2.0
 
-Adapted Lisp logo licensed under CC-BY-SA 4.0 License by
-Common-Lisp.Net maintainers (png) and Jooja (svg)
+Scala logo licensed under the Apache License 2.0 by Lightbend, Inc.
+Files: text-x-scala
+https://github.com/lightbend/cloudflow/
+http://www.apache.org/licenses/LICENSE-2.0
+
+
+=== Creative Commons Attribution-ShareAlike 4.0 International (CC-BY-SA-4.0)  ===
+
+Lisp logo licensed under CC-BY-SA 4.0 License by Jooja
+Jooja's SVG adapted from the PNG logo by Common-Lisp.Net maintainers
+Files: text-x-common-lisp
+https://common-lisp.net/
 https://commons.wikimedia.org/wiki/User:Jooja
 https://commons.wikimedia.org/wiki/File:Lisp_logo.svg
 https://creativecommons.org/licenses/by/4.0/
 
-Adapted Rust logo licensed under CC-BY-4.0 License by the Rust Foundation
+Perl sillhoutte and Snap Store sources licensed under CC-BY-SA 4.0 by Yaru/Jupi007
+Files: application-x-perl
+https://github.com/ubuntu/yaru
+https://github.com/Jupi007
+https://creativecommons.org/licenses/by-sa/4.0/
+
+
+=== Creative Commons Attribution 4.0 International (CC-BY-4.0) ===
+
+Rust logo licensed under CC-BY-4.0 License by the Rust Foundation
+Files: text-rust
 https://foundation.rust-lang.org/policies/logo-policy-and-media-guide/
 https://creativecommons.org/licenses/by/4.0/
 
-Perl sillhoutte and Snap Store sources licensed under CC-BY-SA 4.0 International by Yaru/Jupi007
-https://creativecommons.org/licenses/by-sa/4.0/
-https://github.com/ubuntu/yaru
-https://github.com/Jupi007
 
-VPN/Loading animation icons from Paper (CC-BY-SA-4.0) and Papirus (GPL3) icon themes
+=== GNU General Public License 3.0 ===
+
+VPN/Loading animation icons adapted from the Papirus (GPL3) icon theme
+originally from the Paper icon theme by Sam Hewitt.
+Files: nm-vpn-connecting*, nm-stage*-connecting
+https://icons.samuelhewitt.com/
 https://github.com/snwh/paper-icon-theme
 https://github.com/PapirusDevelopmentTeam/papirus-icon-theme
+https://www.gnu.org/licenses/gpl-3.0.en.html
 
-Scala logo licensed under the Creative Commons Attribution 4.0 International license by Lightbend, Inc.
-https://creativecommons.org/licenses/by/4.0/
+------------------------------------------------------------------
+------------------------------------------------------------------
 
-Crystal logo licensed under the Apache License, Version 2.0.
-Copyright © 2012 Manas Technology Solutions 
-https://crystal-lang.org/media/
-https://www.apache.org/licenses/LICENSE-2.0
+Previous versions of this icon theme used icons, or icon elements,
+from the following themes. These themes also helped inspire many
+of the icons in this set. While these icons and elements are no
+longer used, we'd like to credit these projects and thank the artists.
+
+The GNOME icon theme.
+You can visit the GNOME website here:
+https://www.gnome.org
+
+The Tango icon theme.
+You can find the Tango icon theme here:
+https://gitlab.freedesktop.org/tango/tango-icon-theme
+
+The Humanity icon theme.
+You can visit the Humanity website here:
+https://launchpad.net/ubuntu/+source/humanity-icon-theme