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.

1998/banks/README.md

@@ -185,3 +185,12 @@ the simulator expects.
 The best advice is to set time step size to your system timer
 resolution.  Try a longer period if you're getting too much
 flicker.
+
+## Copyright and CC BY-SA 4.0 License:
+
+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:
+
+    Creative Commons Attribution-ShareAlike 4.0 International (CC BY-SA 4.0)
+
+For more information, see: https://creativecommons.org/licenses/by-sa/4.0/

1998/bas1/README.md

@@ -75,3 +75,11 @@ happens.  (But note that the program only guarantees that there
 actually is a route from entrance to exit if you run it without
 command line arguments.)
 
+## Copyright and CC BY-SA 4.0 License:
+
+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:
+
+    Creative Commons Attribution-ShareAlike 4.0 International (CC BY-SA 4.0)
+
+For more information, see: https://creativecommons.org/licenses/by-sa/4.0/

1998/bas2/README.md

@@ -45,3 +45,12 @@ done by matching the bit patterns.  Minor obfuscations are:
 the character).
 
 - ? and || instead of if statements.
+
+## Copyright and CC BY-SA 4.0 License:
+
+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:
+
+    Creative Commons Attribution-ShareAlike 4.0 International (CC BY-SA 4.0)
+
+For more information, see: https://creativecommons.org/licenses/by-sa/4.0/

1998/chaos/README.md

@@ -80,3 +80,12 @@ The object will "bounce" off the camera, but the result (some points
 in front, some reflected from the rear) looks really odd.  And it
 sometimes hangs.  So just don't fly through objects.  You'll be
 happier.
+
+## Copyright and CC BY-SA 4.0 License:
+
+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:
+
+    Creative Commons Attribution-ShareAlike 4.0 International (CC BY-SA 4.0)
+
+For more information, see: https://creativecommons.org/licenses/by-sa/4.0/

1998/df/README.md

@@ -142,3 +142,12 @@ but still is declared before main(). The `5[O]()` in main() calls
 this function.  Similarly, Most indexing operations have been
 changed to this form; and I tried to write each such operation
 different.
+
+## Copyright and CC BY-SA 4.0 License:
+
+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:
+
+    Creative Commons Attribution-ShareAlike 4.0 International (CC BY-SA 4.0)
+
+For more information, see: https://creativecommons.org/licenses/by-sa/4.0/

1998/dlowe/README.md

@@ -80,3 +80,12 @@ Suggested uses: add to your MANROFFSEQ environment variable for man page
 enjoyment; use it to turn the GPL into the PPL; see what happens when you
 run perl4 programs after they've been run through it; "encrypt" sensitive
 (but unnecessary) documents...
+
+## Copyright and CC BY-SA 4.0 License:
+
+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:
+
+    Creative Commons Attribution-ShareAlike 4.0 International (CC BY-SA 4.0)
+
+For more information, see: https://creativecommons.org/licenses/by-sa/4.0/

1998/dloweneil/README.md

@@ -130,3 +130,12 @@ places.
 
 
 Good Luck!
+
+## Copyright and CC BY-SA 4.0 License:
+
+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:
+
+    Creative Commons Attribution-ShareAlike 4.0 International (CC BY-SA 4.0)
+
+For more information, see: https://creativecommons.org/licenses/by-sa/4.0/

1998/dorssel/README.md

@@ -103,3 +103,12 @@ is the same as
 program.  For an obfuscated spoiler, try
 
           ./dorssel < dorssel.hint 
+
+## Copyright and CC BY-SA 4.0 License:
+
+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:
+
+    Creative Commons Attribution-ShareAlike 4.0 International (CC BY-SA 4.0)
+
+For more information, see: https://creativecommons.org/licenses/by-sa/4.0/

1998/fanf/README.md

@@ -388,3 +388,12 @@ We can then check that this evaluates to the expected result:
 
     Wadler, P., 1995. How to Declare an Imperative. Proceedings of the ACM
     International Logic Programming Symposium, 1995.
+
+## Copyright and CC BY-SA 4.0 License:
+
+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:
+
+    Creative Commons Attribution-ShareAlike 4.0 International (CC BY-SA 4.0)
+
+For more information, see: https://creativecommons.org/licenses/by-sa/4.0/

1998/schnitzi/README.md

@@ -103,3 +103,12 @@ The only function ever called is "O", but "O" is just set to point to
 other functions all the time.  Or, almost all the time.
 
 So how does 'h' get set, and what to?
+
+## Copyright and CC BY-SA 4.0 License:
+
+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:
+
+    Creative Commons Attribution-ShareAlike 4.0 International (CC BY-SA 4.0)
+
+For more information, see: https://creativecommons.org/licenses/by-sa/4.0/

1998/schweikh1/README.md

@@ -212,3 +212,12 @@
 
     From the goals: "To stress C compilers with unusual code."
     That describes exactly my modest attempts...
+
+## Copyright and CC BY-SA 4.0 License:
+
+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:
+
+    Creative Commons Attribution-ShareAlike 4.0 International (CC BY-SA 4.0)
+
+For more information, see: https://creativecommons.org/licenses/by-sa/4.0/

1998/schweikh2/README.md

@@ -179,3 +179,12 @@ is fully standard-compliant.
     load, number and temporal distribution of asynchronous events and
     last but not least the phase of the moon. God _does_ play dice.
     Type yarng and watch Him roll.
+
+## Copyright and CC BY-SA 4.0 License:
+
+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:
+
+    Creative Commons Attribution-ShareAlike 4.0 International (CC BY-SA 4.0)
+
+For more information, see: https://creativecommons.org/licenses/by-sa/4.0/

1998/schweikh3/README.md

@@ -198,3 +198,12 @@ Notice that the tool finds a duplicate file, that of the man page.
     the same size (on systems where sizeof (char *) == 4, or 4096 when
     sizeof (char *) == 8), increase the manifest constant 32767 on line
     31.
+
+## Copyright and CC BY-SA 4.0 License:
+
+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:
+
+    Creative Commons Attribution-ShareAlike 4.0 International (CC BY-SA 4.0)
+
+For more information, see: https://creativecommons.org/licenses/by-sa/4.0/

1998/tomtorfs/README.md

@@ -100,3 +100,12 @@
 
        Ross N. Williams, whose CRC guide was very useful to me
        for writing this. You can find it as CRC.TXT in Snippets.
+
+## Copyright and CC BY-SA 4.0 License:
+
+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:
+
+    Creative Commons Attribution-ShareAlike 4.0 International (CC BY-SA 4.0)
+
+For more information, see: https://creativecommons.org/licenses/by-sa/4.0/