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/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;