Merge pull request #171 from the-mikedavis/pipe-codefence-fix

minor: Close codeblock in `low_lewel::pipe` docs

Author: vorner

src/low_level/pipe.rs

@@ -73,6 +73,7 @@
 //!     println!("Happily terminating");
 //!     Ok(())
 //! }
+//! ```
 
 use std::io::{Error, ErrorKind};
 use std::os::unix::io::{AsRawFd, IntoRawFd, RawFd};