Adding crate-level documentation (#9)

README.md

@@ -1,6 +1,35 @@
 # voprf ![Build Status](https://github.com/novifinancial/voprf/workflows/Rust%20CI/badge.svg)
 An implementation of a (verifiable) oblivious pseudorandom function (VOPRF)
 
+A VOPRF is a verifiable oblivious pseudorandom function, a protocol between a client and a server. The regular (non-verifiable) OPRF is also supported in this implementation.
+
+This implementation is based on the [Internet Draft for VOPRF](https://github.com/cfrg/draft-irtf-cfrg-voprf).
+
+Documentation
+-------------
+
+The API can be found [here](https://docs.rs/voprf/) along with an example for usage.
+
+Installation
+------------
+
+Add the following line to the dependencies of your `Cargo.toml`:
+
+```
+voprf = "0.1.0"
+```
+
+### Minimum Supported Rust Version
+
+Rust **1.51** or higher.
+
+Contributors
+------------
+
+The author of this code is Kevin Lewi
+([@kevinlewi](https://github.com/kevinlewi)) .
+To learn more about contributing to this project, [see this document](./CONTRIBUTING.md).
+
 License
 -------