Restore License section from main

Author: neatudarius

README.md

@@ -13,10 +13,20 @@ This repository implements `std::optional` extensions targeting C++26. The `Bema
 
 ## License
 
-Source, documentation and associated papers are licensed with the Apache 2.0 license with LLVM exceptions.
+Source is licensed with the Apache 2.0 license with LLVM exceptions
 
 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
 
+Documentation and associated papers are licensed with the Creative Commons Attribution 4.0 International license.
+
+// SPDX-License-Identifier: CC-BY-4.0
+
+The intent is that the source and documentation are available for use by people implementing their own optional types as well as people using the optional presented here as-is.
+
+The README itself is licesed with CC0 1.0 Universal. Copy the contents and incorporate in your own work as you see fit.
+
+// SPDX-License-Identifier: CC0-1.0
+
 ## Examples
 
 Full runable examples can be found in `examples/` - please check [./examples/README.md](./examples/README.md).