add io::prelude

Signed-off-by: Yoshua Wuyts <yoshuawuyts@gmail.com>

src/io/mod.rs

@@ -20,6 +20,8 @@
 //! # Ok(()) }) }
 //! ```
 
+pub mod prelude;
+
 #[doc(inline)]
 pub use std::io::{Error, ErrorKind, Result, SeekFrom};
 

src/io/prelude.rs

@@ -0,0 +1,11 @@
+//! The I/O Prelude
+//!
+//! The purpose of this module is to alleviate imports of many common I/O traits
+//! by adding a glob import to the top of I/O heavy modules:
+//!
+//! ```
+//! # #![allow(unused_imports)]
+//! use async_std::io::prelude::*;
+//! ```
+
+pub use super::{BufRead, Read, Seek, Write};