chore: added license, codecov badge and contrib rules

Cargo.toml

@@ -2,6 +2,7 @@
 name = "oidc-authorizer"
 version = "0.1.0"
 edition = "2021"
+license = "MIT"
 
 # Starting in Rust 1.62 you can use `cargo add` to add dependencies 
 # to your project.

LICENSE

@@ -0,0 +1,21 @@
+MIT License Copyright (c) 2023 Luciano Mammino
+
+Permission is hereby granted,
+free of charge, to any person obtaining a copy of this software and associated
+documentation files (the "Software"), to deal in the Software without
+restriction, including without limitation the rights to use, copy, modify, merge,
+publish, distribute, sublicense, and/or sell copies of the Software, and to
+permit persons to whom the Software is furnished to do so, subject to the
+following conditions:
+
+The above copyright notice and this permission notice
+(including the next paragraph) shall be included in all copies or substantial
+portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF
+ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO
+EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR
+OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+THE SOFTWARE.

README.md

@@ -1,6 +1,7 @@
 # oidc-authorizer
 
 [![Rust](https://github.com/lmammino/oidc-authorizer/actions/workflows/rust.yml/badge.svg)](https://github.com/lmammino/oidc-authorizer/actions/workflows/rust.yml)
+[![codecov](https://codecov.io/gh/lmammino/oidc-authorizer/graph/badge.svg?token=P9bsrl4YQB)](https://codecov.io/gh/lmammino/oidc-authorizer)
 
 
 A high-performance token-based API Gateway authorizer Lambda that can validate OIDC-issued JWT tokens.
@@ -10,8 +11,20 @@ A high-performance token-based API Gateway authorizer Lambda that can validate O
 
 - TODO: document use case
 - TODO: document installation process
-- TODO: license and contribution rules
 - TODO: document supported algorithms
 - TODO: document validation flow
 - TODO: document configuration options
 - TODO: document what gets added into the context
+- TODO: benchmarks
+
+
+## Contributing
+
+Everyone is very welcome to contribute to this project.
+You can contribute just by submitting bugs or suggesting improvements by
+[opening an issue on GitHub](https://github.com/lmammino/oidc-authorizer/issues).
+
+
+## License
+
+Licensed under [MIT License](LICENSE). © Luciano Mammino.