put all README.md files under CC BY-SA 4.0 License

This will make is easier for others to share README.md
files while requiring them to attribute the file
when using it.

2018/hou/README.md

@@ -46,10 +46,11 @@ This entry takes such decadence to an extreme. It just calls a bunch of librarie
 
 As one would expect from such an approach, this program is much more resource intensive than it should be. And one needs a C99-compatible libc (with the common UNIX stuff) to build this and an HTML5-compatible browser to open the result. And it terminates with an assertion failure, but who cares if the web page is already generated?
 
-## Copyright:
+## Copyright and CC BY-SA 4.0 License:
 
-(c) Copyright 1984-2018, [Leo Broukhis, Simon Cooper, Landon Curt Noll][judges] - All rights reserved
-This work is licensed under a [Creative Commons Attribution-ShareAlike 3.0 Unported License][cc].
+This file is Copyright (c) 2023 by Landon Curt Noll.  All Rights Reserved.
+You are free to share and adapt this file under the terms this license:
 
-[judges]: http://www.ioccc.org/judges.html
-[cc]: http://creativecommons.org/licenses/by-sa/3.0/
+    Creative Commons Attribution-ShareAlike 4.0 International (CC BY-SA 4.0)
+
+For more information, see: https://creativecommons.org/licenses/by-sa/4.0/