docs: add License and Contributing sections to repo top-level README

- moved license files up to repo top-level directory
- minor cleanup of bdk/README.md License and Contribution sections

Author: notmandatory

crates/bdk/LICENSE renamed to LICENSE

@@ -66,3 +66,19 @@ cargo update -p tempfile --precise "3.6.0"
 # rustls 0.21.2 has MSRV 1.60.0+
 cargo update -p rustls:0.21.6 --precise "0.21.1"
 ```
+
+## License
+
+Licensed under either of
+
+* Apache License, Version 2.0, ([LICENSE-APACHE](LICENSE-APACHE) or <https://www.apache.org/licenses/LICENSE-2.0>)
+* MIT license ([LICENSE-MIT](LICENSE-MIT) or <https://opensource.org/licenses/MIT>)
+
+at your option.
+
+### Contribution
+
+Unless you explicitly state otherwise, any contribution intentionally
+submitted for inclusion in the work by you, as defined in the Apache-2.0
+license, shall be dual licensed as above, without any additional terms or
+conditions.

crates/bdk/LICENSE-APACHE renamed to LICENSE-APACHE

@@ -206,18 +206,17 @@ cargo test
 
 Licensed under either of
 
- * Apache License, Version 2.0
-   ([LICENSE-APACHE](LICENSE-APACHE) or <https://www.apache.org/licenses/LICENSE-2.0>)
- * MIT license
-   ([LICENSE-MIT](LICENSE-MIT) or <https://opensource.org/licenses/MIT>)
+* Apache License, Version 2.0, ([LICENSE-APACHE](../../LICENSE-APACHE) or <https://www.apache.org/licenses/LICENSE-2.0>)
+* MIT license ([LICENSE-MIT](../../LICENSE-MIT) or <https://opensource.org/licenses/MIT>)
 
 at your option.
 
-## Contribution
+### Contribution
 
-Unless you explicitly state otherwise, any contribution intentionally submitted
-for inclusion in the work by you, as defined in the Apache-2.0 license, shall be
-dual licensed as above, without any additional terms or conditions.
+Unless you explicitly state otherwise, any contribution intentionally
+submitted for inclusion in the work by you, as defined in the Apache-2.0
+license, shall be dual licensed as above, without any additional terms or
+conditions.
 
 [`bdk_chain`]: https://docs.rs/bdk_chain/latest
 [`bdk_file_store`]: https://docs.rs/bdk_file_store/latest