update licensing for me

LICENSE.txt

@@ -1,3 +1,47 @@
+License of source code specific to this subgame
+-----------------------------------------------
+Copyright (C) 2020 mckaygerhard
+Copyright (C) 2020-2023 mckayshirou
+
+Attribution-ShareAlike 3.0 Unported (CC BY-SA 3.0)
+http://creativecommons.org/licenses/by-sa/3.0/
+
+This is a human-readable summary of (and not a substitute for) the license. 
+Disclaimer. You are free to:
+
+    Share — copy and redistribute the material in any medium or format
+    Adapt — remix, transform, and build upon the material
+    for any purpose, even commercially.
+
+This license is acceptable for Free Cultural Works.
+
+    The licensor cannot revoke these freedoms as long as you follow the 
+    license terms.
+
+Under the following terms:
+
+    Attribution — You must give appropriate credit, provide a link to the license, 
+    and indicate if changes were made. You may do so in any reasonable manner, 
+    but not in any way that suggests the licensor endorses you or your use.
+
+    ShareAlike — If you remix, transform, or build upon the material, you must 
+    distribute your contributions under the same license as the original.
+
+    No additional restrictions — You may not apply legal terms or technological 
+    measures that legally restrict others from doing anything the license permits.
+
+Notices:
+
+    You do not have to comply with the license for elements of the material in 
+    the public domain or where your use is permitted by an applicable exception 
+    or limitation.
+
+    No warranties are given. The license may not give you all of the permissions 
+    necessary for your intended use. For example, other rights such as publicity, 
+    privacy, or moral rights may limit how you use the material.
+
+
+
 License of media (textures and sounds)
 --------------------------------------
 Copyright (C) 2010-2012 celeron55, Perttu Ahola <celeron55@gmail.com>

README.md

@@ -64,6 +64,6 @@ To download you can play this game with the following minetest engines:
 ## Licensing
 
 * (c) 2020 mckaygerhard
-* (c) 2020 mckayshirou
+* (c) 2023 mckayshirou
 
 CC-BY-SA-NC 4.0 (c) MckAY Lenz, See `LICENSE.txt`