Add note about crate rename

rust-bindings/rust/README.md

@@ -9,6 +9,8 @@ libostree is both a shared library and suite of command line tools that combines
 a "git-like" model for committing and downloading bootable filesystem trees,
 along with a layer for deploying them and managing the bootloader configuration.
 
+> **Note**: this crate was renamed from the `libostree` crate.
+
 ## Status
 The bindings are quite incomplete right now. Most of it can be autogenerated,
 but I simply turned on what I needed and left the rest for later.