bip340: Change license of code and test vectors

See https://github.com/bitcoin/bips/commits/master/bip-0340 for a list
of contributors. I have obtained permission to do this change from all
contributors in private. Nevertheless, it would be good to get an ACK
from every contributor in order to have publicly available evidence.

 - [ ] @sipa
 - [ ] @jonasnick
 - [ ] @theStack
 - [ ] @ysangkok

I haven't contacted @Sajjon and @satsie, whose contributions constitute
of fixing not more than two typos and are thus below the threshold of
originality required for copyright to be applicable.

bip-0340.mediawiki

@@ -9,6 +9,9 @@
   Status: Final
   Type: Standards Track
   License: BSD-2-Clause
+  License-Code: BSD-2-Clause
+                MIT
+                CC0-1.0
   Created: 2020-01-19
   Post-History: 2018-07-06: https://lists.linuxfoundation.org/pipermail/bitcoin-dev/2018-July/016203.html [bitcoin-dev] Schnorr signatures BIP
 </pre>
@@ -284,7 +287,10 @@ Blind Schnorr signatures could for example be used in [https://github.com/Elemen
 
 == Test Vectors and Reference Code ==
 
-For development and testing purposes, we provide a [[bip-0340/test-vectors.csv|collection of test vectors in CSV format]] and a naive, highly inefficient, and non-constant time [[bip-0340/reference.py|pure Python 3.7 reference implementation of the signing and verification algorithm]].
+For development and testing purposes, we provide a [[bip-0340/test-vectors.csv|collection of test vectors in CSV format]],
+a naive, highly inefficient, and non-constant time [[bip-0340/reference.py|pure Python 3.7 reference implementation of the signing and verification algorithm]]
+as well as the [[bip340/test-vectors.py|script used to generate the test vectors]]
+under the BSD-2-Clause License, or the MIT License, or CC0 1.0, at your choice.
 The reference implementation is for demonstration purposes only and not to be used in production environments.
 
 == Changelog ==
@@ -294,6 +300,7 @@ To help implementers understand updates to this BIP, we keep a list of substanti
 * 2022-08: Fix function signature of lift_x in reference code
 * 2023-04: Allow messages of arbitrary size
 * 2024-05: Update "Applications" section with more recent references
+* 2025-04: Change license of test vectors and code
 
 == Footnotes ==
 

bip-0340/LICENSE

@@ -0,0 +1,11 @@
+BSD-2-Clause OR MIT OR CC0-1.0
+
+The contents of this directory are provided under one of the following sets of
+terms, at your choice:
+
+ - The BSD-2-Clause License
+   https://opensource.org/license/BSD-2-Clause
+ - The MIT License
+   https://opensource.org/license/MIT
+ - CC0 1.0
+   https://creativecommons.org/publicdomain/zero/1.0/