fix off-by-one error

Author: bmusin

src/libstd/io/buffered.rs

@@ -316,8 +316,8 @@ impl<R: Seek> Seek for BufReader<R> {
 ///
 /// let mut stream = TcpStream::connect("127.0.0.1:34254").unwrap();
 ///
-/// for i in 1..10 {
-///     stream.write(&[i]).unwrap();
+/// for i in 0..10 {
+///     stream.write(&[i+1]).unwrap();
 /// }
 /// ```
 ///
@@ -332,8 +332,8 @@ impl<R: Seek> Seek for BufReader<R> {
 ///
 /// let mut stream = BufWriter::new(TcpStream::connect("127.0.0.1:34254").unwrap());
 ///
-/// for i in 1..10 {
-///     stream.write(&[i]).unwrap();
+/// for i in 0..10 {
+///     stream.write(&[i+1]).unwrap();
 /// }
 /// ```
 ///