Utilize fewer reexports

In regards to:

https://github.com/rust-lang/rust/issues/19253#issuecomment-64836729

This commit:

* Changes the #deriving code so that it generates code that utilizes fewer
  reexports (in particur Option::* and Result::*), which is necessary to
  remove those reexports in the future
* Changes other areas of the codebase so that fewer reexports are utilized

src/libstd/io/buffered.rs

@@ -16,8 +16,9 @@ use cmp;
 use io::{Reader, Writer, Stream, Buffer, DEFAULT_BUF_SIZE, IoResult};
 use iter::ExactSizeIterator;
 use ops::Drop;
-use option::{Some, None, Option};
-use result::{Ok, Err};
+use option::Option;
+use option::Option::{Some, None};
+use result::Result::{Ok, Err};
 use slice::{SlicePrelude};
 use slice;
 use vec::Vec;

src/libstd/io/comm_adapters.rs

@@ -12,8 +12,8 @@ use clone::Clone;
 use cmp;
 use comm::{Sender, Receiver};
 use io;
-use option::{None, Some};
-use result::{Ok, Err};
+use option::Option::{None, Some};
+use result::Result::{Ok, Err};
 use slice::{bytes, CloneSliceAllocPrelude, SlicePrelude};
 use super::{Buffer, Reader, Writer, IoResult};
 use vec::Vec;

src/libstd/io/extensions.rs

@@ -19,9 +19,10 @@ use io::{IoError, IoResult, Reader};
 use io;
 use iter::Iterator;
 use num::Int;
-use option::{Option, Some, None};
+use option::Option;
+use option::Option::{Some, None};
 use ptr::RawPtr;
-use result::{Ok, Err};
+use result::Result::{Ok, Err};
 use slice::{SlicePrelude, AsSlice};
 
 /// An iterator that reads a single byte on each iteration,

src/libstd/io/fs.rs

@@ -59,10 +59,11 @@ use io::{Read, Truncate, ReadWrite, Append};
 use io::UpdateIoError;
 use io;
 use iter::{Iterator, Extend};
-use option::{Some, None, Option};
+use option::Option;
+use option::Option::{Some, None};
 use path::{Path, GenericPath};
 use path;
-use result::{Err, Ok};
+use result::Result::{Err, Ok};
 use slice::SlicePrelude;
 use string::String;
 use vec::Vec;

src/libstd/io/mem.rs

@@ -15,8 +15,8 @@
 #![allow(deprecated)]
 
 use cmp::min;
-use option::None;
-use result::{Err, Ok};
+use option::Option::None;
+use result::Result::{Err, Ok};
 use io;
 use io::{Reader, Writer, Seek, Buffer, IoError, SeekStyle, IoResult};
 use slice::{mod, AsSlice, SlicePrelude};

src/libstd/io/mod.rs

@@ -233,10 +233,12 @@ use int;
 use iter::{Iterator, IteratorExt};
 use mem::transmute;
 use ops::{BitOr, BitXor, BitAnd, Sub, Not};
-use option::{Option, Some, None};
+use option::Option;
+use option::Option::{Some, None};
 use os;
 use boxed::Box;
-use result::{Ok, Err, Result};
+use result::Result;
+use result::Result::{Ok, Err};
 use sys;
 use slice::{AsSlice, SlicePrelude};
 use str::{Str, StrPrelude};

src/libstd/io/net/addrinfo.rs

@@ -22,7 +22,8 @@ pub use self::Protocol::*;
 use iter::IteratorExt;
 use io::{IoResult};
 use io::net::ip::{SocketAddr, IpAddr};
-use option::{Option, Some, None};
+use option::Option;
+use option::Option::{Some, None};
 use sys;
 use vec::Vec;
 

src/libstd/io/net/ip.rs

@@ -21,8 +21,9 @@ use fmt;
 use io::{mod, IoResult, IoError};
 use io::net;
 use iter::{Iterator, IteratorExt};
-use option::{Option, None, Some};
-use result::{Ok, Err};
+use option::Option;
+use option::Option::{None, Some};
+use result::Result::{Ok, Err};
 use str::{FromStr, StrPrelude};
 use slice::{CloneSlicePrelude, SlicePrelude};
 use vec::Vec;

src/libstd/io/net/mod.rs

@@ -11,8 +11,8 @@
 //! Networking I/O
 
 use io::{IoError, IoResult, InvalidInput};
-use option::None;
-use result::{Ok, Err};
+use option::Option::None;
+use result::Result::{Ok, Err};
 use self::ip::{SocketAddr, ToSocketAddr};
 
 pub use self::addrinfo::get_host_addresses;

src/libstd/io/net/tcp.rs

@@ -19,11 +19,12 @@
 
 use clone::Clone;
 use io::IoResult;
-use result::Err;
+use result::Result::Err;
 use io::net::ip::{SocketAddr, ToSocketAddr};
 use io::{Reader, Writer, Listener, Acceptor};
 use io::{standard_error, TimedOut};
-use option::{None, Some, Option};
+use option::Option;
+use option::Option::{None, Some};
 use time::Duration;
 
 use sys::tcp::TcpStream as TcpStreamImp;

src/libstd/io/net/udp.rs

@@ -19,7 +19,7 @@ use clone::Clone;
 use io::net::ip::{SocketAddr, IpAddr, ToSocketAddr};
 use io::{Reader, Writer, IoResult};
 use option::Option;
-use result::{Ok, Err};
+use result::Result::{Ok, Err};
 use sys::udp::UdpSocket as UdpSocketImp;
 use sys_common;
 

src/libstd/io/result.rs

@@ -15,7 +15,7 @@
 //! as a `Reader` without unwrapping the result first.
 
 use clone::Clone;
-use result::{Ok, Err};
+use result::Result::{Ok, Err};
 use super::{Reader, Writer, Listener, Acceptor, Seek, SeekStyle, IoResult};
 
 impl<W: Writer> Writer for IoResult<W> {

src/libstd/io/stdio.rs

@@ -37,9 +37,10 @@ use io::{Reader, Writer, IoResult, IoError, OtherIoError, Buffer,
 use kinds::Send;
 use libc;
 use mem;
-use option::{Option, Some, None};
+use option::Option;
+use option::Option::{Some, None};
 use ops::{Deref, DerefMut};
-use result::{Ok, Err};
+use result::Result::{Ok, Err};
 use rustrt;
 use rustrt::local::Local;
 use rustrt::task::Task;

src/libstd/io/tempfile.rs

@@ -14,10 +14,11 @@ use io::{fs, IoResult};
 use io;
 use libc;
 use ops::Drop;
-use option::{Option, None, Some};
+use option::Option;
+use option::Option::{None, Some};
 use os;
 use path::{Path, GenericPath};
-use result::{Ok, Err};
+use result::Result::{Ok, Err};
 use sync::atomic;
 
 /// A wrapper for a path to temporary directory implementing automatic