Auto merge of #121 - jrmuizel:uuid, r=jdm

Add support for CFUUID

<!-- Reviewable:start -->
This change is [<img src="https://reviewable.io/review_button.svg" height="34" align="absmiddle" alt="Reviewable"/>](https://reviewable.io/reviews/servo/core-foundation-rs/121)
<!-- Reviewable:end -->

core-foundation-sys/src/lib.rs

@@ -26,3 +26,4 @@ pub mod runloop;
 pub mod set;
 pub mod string;
 pub mod url;
+pub mod uuid;

core-foundation-sys/src/uuid.rs

@@ -0,0 +1,43 @@
+// Copyright 2013-2015 The Servo Project Developers. See the COPYRIGHT
+// file at the top-level directory of this distribution.
+//
+// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
+// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
+// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
+// option. This file may not be copied, modified, or distributed
+// except according to those terms.
+use libc::c_void;
+
+use base::CFAllocatorRef;
+
+#[repr(C)]
+pub struct __CFUUID(c_void);
+
+pub type CFUUIDRef = *const __CFUUID;
+
+#[repr(C)]
+pub struct CFUUIDBytes {
+    byte0:  u8,
+    byte1:  u8,
+    byte2:  u8,
+    byte3:  u8,
+    byte4:  u8,
+    byte5:  u8,
+    byte6:  u8,
+    byte7:  u8,
+    byte8:  u8,
+    byte9:  u8,
+    byte10: u8,
+    byte11: u8,
+    byte12: u8,
+    byte13: u8,
+    byte14: u8,
+    byte15: u8
+}
+
+extern {
+    /*
+     * CFUUID.h
+     */
+    pub fn CFUUIDCreateFromUUIDBytes(allocator: CFAllocatorRef, bytes: CFUUIDBytes) -> CFUUIDRef;
+}