clean up the licenses section of the readme

README.md

@@ -187,17 +187,13 @@ bindings](https://github.com/sken77/BLAKE3jni).
 
 Please see [CONTRIBUTING.md](CONTRIBUTING.md).
 
-## Intellectual property
+## Licenses
 
-The Rust code is copyright Jack O'Connor, 2019-2020. The C code is
-copyright Samuel Neves and Jack O'Connor, 2019-2020. The assembly code
-is copyright Samuel Neves, 2019-2020.
+This work is released into the public domain with [CC0 1.0](./LICENSE_CC0).
+Alternatively, it is licensed under any of the following:
 
-This code is multi-licensed under
-
-* [CC0](./LICENCE_CC0)
-* [Apache 2.0](./LICENSE_A2).
-* [Apache 2.0 with LLVM exceptions](./LICENSE_A2LLVM).
+* [Apache 2.0](./LICENSE_A2)
+* [Apache 2.0 with LLVM exceptions](./LICENSE_A2LLVM)
 
 
 ## Adoption & deployment