chore: apply rustfmt to all crates (#917)

tokio-io/src/allow_std.rs

@@ -1,6 +1,6 @@
-use {AsyncRead, AsyncWrite};
 use futures::{Async, Poll};
 use std::{fmt, io};
+use {AsyncRead, AsyncWrite};
 
 /// A simple wrapper type which allows types that only implement
 /// `std::io::Read` or `std::io::Write` to be used in contexts which expect
@@ -37,7 +37,10 @@ impl<T> AllowStdIo<T> {
     }
 }
 
-impl<T> io::Write for AllowStdIo<T> where T: io::Write {
+impl<T> io::Write for AllowStdIo<T>
+where
+    T: io::Write,
+{
     fn write(&mut self, buf: &[u8]) -> io::Result<usize> {
         self.0.write(buf)
     }
@@ -52,13 +55,19 @@ impl<T> io::Write for AllowStdIo<T> where T: io::Write {
     }
 }
 
-impl<T> AsyncWrite for AllowStdIo<T> where T: io::Write {
+impl<T> AsyncWrite for AllowStdIo<T>
+where
+    T: io::Write,
+{
     fn shutdown(&mut self) -> Poll<(), io::Error> {
         Ok(Async::Ready(()))
     }
 }
 
-impl<T> io::Read for AllowStdIo<T> where T: io::Read {
+impl<T> io::Read for AllowStdIo<T>
+where
+    T: io::Read,
+{
     fn read(&mut self, buf: &mut [u8]) -> io::Result<usize> {
         self.0.read(buf)
     }
@@ -75,7 +84,10 @@ impl<T> io::Read for AllowStdIo<T> where T: io::Read {
     }
 }
 
-impl<T> AsyncRead for AllowStdIo<T> where T: io::Read {
+impl<T> AsyncRead for AllowStdIo<T>
+where
+    T: io::Read,
+{
     // TODO: override prepare_uninitialized_buffer once `Read::initializer` is stable.
     // See rust-lang/rust #42788
 }