add release expectation to readme

Author: zachschuermann

README.md

@@ -105,6 +105,11 @@ and then checking what version of `object_store` it depends on.
 There are some example programs showing how `delta-kernel-rs` can be used to interact with delta
 tables. They live in the [`kernel/examples`](kernel/examples) directory.
 
+## Release cadence
+
+We attempt to release the crate every 2 weeks (in an effort to keep latency between merge and
+shipping low); though, sometimes releases may take longer.
+
 ## Development
 
 delta-kernel-rs is still under heavy development but follows conventions adopted by most Rust
@@ -173,4 +178,4 @@ Some design principles which should be considered:
 [cargo-llvm-cov]: https://github.com/taiki-e/cargo-llvm-cov
 [FFI]: ffi/
 [Arrow]: https://arrow.apache.org/rust/arrow/index.html
-[Tokio]: https://tokio.rs/
+[Tokio]: https://tokio.rs/