Add a note about release support.

Author: sfackler

README.md

@@ -1,9 +1,21 @@
 # rust-openssl
 
-[![CircleCI](https://circleci.com/gh/sfackler/rust-openssl.svg?style=shield)](https://circleci.com/gh/sfackler/rust-openssl) [![Build status](https://ci.appveyor.com/api/projects/status/d1knobws948pyynk/branch/master?svg=true)](https://ci.appveyor.com/project/sfackler/rust-openssl/branch/master) [![crates.io](https://img.shields.io/crates/v/openssl.svg)](https://crates.io/crates/openssl)
+[![CircleCI](https://circleci.com/gh/sfackler/rust-openssl.svg?style=shield)](https://circleci.com/gh/sfackler/rust-openssl)
+[![Build status](https://ci.appveyor.com/api/projects/status/d1knobws948pyynk/branch/master?svg=true)](https://ci.appveyor.com/project/sfackler/rust-openssl/branch/master)
+[![crates.io](https://img.shields.io/crates/v/openssl.svg)](https://crates.io/crates/openssl)
+
+OpenSSL bindings for the Rust programming language.
 
 [Documentation](https://docs.rs/openssl).
 
+## Release Support
+
+The current supported release is 0.10.
+
+New major versions will be published at most once per year. After a new
+release, the previous major version will be partially supported with bug
+fixes for 3 months, after which support will be dropped entirely.
+
 ### Contribution
 
 Unless you explicitly state otherwise, any contribution intentionally