Add license information to README

Cargo.toml

@@ -3,6 +3,7 @@ name = "petal-neighbors"
 version = "0.4.0"
 description = "Nearest neighbor search algorithms including a ball tree and a vantage point tree."
 readme = "README.md"
+documentation = "https://docs.rs/petal-neighbors"
 homepage = "https://github.com/petabi/petal-neighbors"
 repository = "https://github.com/petabi/petal-neighbors"
 license = "Apache-2.0"

README.md

@@ -6,10 +6,6 @@ Nearest neighbor search algorithms including a ball tree and a vantage point tre
 [![Documentation](https://docs.rs/petal-neighbors/badge.svg)](https://docs.rs/petal-neighbors)
 [![Coverage Status](https://codecov.io/gh/petabi/petal-neighbors/branch/master/graphs/badge.svg)](https://codecov.io/gh/petabi/petal-neighbors)
 
-## Requirements
-
-* Rust ≥ 1.37
-
 ## Examples
 
 The following example shows how to find two nearest neighbors in a ball tree.
@@ -23,3 +19,28 @@ let tree = BallTree::euclidean(points).unwrap();
 let (indices, distances) = tree.query(&[3., 3.], 2);
 assert_eq!(indices, &[1, 0]);  // points[1] is the nearest, points[0] the next.
 ```
+
+## Minimum Supported Rust Version
+
+This crate is guaranteed to compile on Rust 1.37 and later.
+
+## License
+
+Copyright 2019-2020 Petabi, Inc.
+
+Licensed under [Apache License, Version 2.0][apache-license] (the "License");
+you may not use this crate except in compliance with the License.
+
+Unless required by applicable law or agreed to in writing, software distributed
+under the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR
+CONDITIONS OF ANY KIND, either express or implied. See [LICENSE](LICENSE) for
+the specific language governing permissions and limitations under the License.
+
+## 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][apache-license], shall be licensed as above, without any additional
+terms or conditions.
+
+[apache-license]: http://www.apache.org/licenses/LICENSE-2.0