remove unused import warnings

src/compiletest/procsrv.rs

@@ -10,14 +10,9 @@
 
 use core::prelude::*;
 
-use core::comm;
-use core::io;
-use core::libc::c_int;
 use core::os;
 use core::run;
 use core::str;
-use core::task;
-use core::vec;
 
 #[cfg(target_os = "win32")]
 fn target_env(lib_path: &str, prog: &str) -> ~[(~str,~str)] {
@@ -74,4 +69,3 @@ pub fn run(lib_path: &str,
         err: str::from_bytes(output.error)
     }
 }
-