Update rust/itertools versions in the doc

Author: Philippe-Cholet

src/lib.rs

@@ -42,8 +42,8 @@
 //!
 //! ## Rust Version
 //!
-//! This version of itertools requires Rust 1.32 or later.
-#![doc(html_root_url="https://docs.rs/itertools/0.8/")]
+//! This version of itertools requires Rust 1.36 or later.
+#![doc(html_root_url="https://docs.rs/itertools/0.11/")]
 
 #[cfg(not(feature = "use_std"))]
 extern crate core as std;