Remove unused imports

src/lib.rs

@@ -56,12 +56,10 @@ extern crate net2;
 use bufstream::BufStream;
 use md5::Md5;
 use std::ascii::AsciiExt;
-use std::borrow::ToOwned;
 use std::cell::{Cell, RefCell};
 use std::collections::{VecDeque, HashMap};
 use std::error::Error as StdError;
 use std::fmt;
-use std::iter::IntoIterator;
 use std::io as std_io;
 use std::io::prelude::*;
 use std::marker::Sync as StdSync;