MonitorID now defined by the implementations

src/x11/mod.rs

@@ -1,4 +1,4 @@
-use {Event, Hints, MonitorID};
+use {Event, Hints};
 use libc;
 use std::{mem, ptr};
 use std::sync::atomics::AtomicBool;
@@ -14,6 +14,8 @@ pub struct Window {
     wm_delete_window: ffi::Atom,
 }
 
+pub struct MonitorID(uint);
+
 impl Window {
     pub fn new(dimensions: Option<(uint, uint)>, title: &str, hints: &Hints, _: Option<MonitorID>)
         -> Result<Window, String>