* A [complete API overhaul](https://github.com/rust-bitcoin/rust-secp256k1/pull/27) to move many runtime errors into compiletime errors
* Update [libsecp256k1 to `1e6f1f5ad5e7f1e3ef79313ec02023902bf8`](https://github.com/rust-bitcoin/rust-secp256k1/pull/32). Should be no visible changes.
* [Remove `PublicKey::new()` and `PublicKey::is_valid()`](https://github.com/rust-bitcoin/rust-secp256k1/pull/37) since `new` was unsafe and it should now be impossible to create invalid `PublicKey` objects through the API
* [Reintroduce serde support](https://github.com/rust-bitcoin/rust-secp256k1/pull/38) behind a feature gate using serde 1.0