remove some unused imports

src/ext/bytes.rs

@@ -8,7 +8,6 @@ use std::ffi::c_void;
 /// Essentially `explicit_bzero()`.
 #[inline(never)]
 pub fn explicit_clear(buffer : &mut[u8]) {
-    use std::ffi::c_void;
     unsafe {
 	std::ptr::write_bytes(buffer.as_mut_ptr() as * mut c_void, 0, buffer.len());
 

src/service/command.rs

@@ -67,8 +67,6 @@ impl Command
     /// Dispose of this `Command`, returning any `Response` that might've already been sent.
     #[inline] pub fn close(mut self) -> Option<Response>
     {
-	use oneshot::error::TryRecvError;
-
 	self.resp.close();
 	self.resp.try_recv().ok().flatten()
     }