add Copy and Clone impls

Author: newpavlov

src/unix/redox/mod.rs

@@ -35,7 +35,13 @@ pub type speed_t = u32;
 pub type suseconds_t = ::c_int;
 pub type tcflag_t = u32;
 pub type time_t = ::c_long;
+
+#[cfg_attr(feature = "extra_traits", derive(Debug))]
 pub enum timezone {}
+impl ::Copy for timezone {}
+impl ::Clone for timezone {
+    fn clone(&self) -> timezone { *self }
+}
 
 s! {
     pub struct addrinfo {