Add style_traits crate to improve crate separation,

closes #7353

components/style_traits/lib.rs

@@ -0,0 +1,27 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+//! This module contains shared types and messages for use by devtools/script.
+//! The traits are here instead of in script so that the devtools crate can be
+//! modified independently of the rest of Servo.
+
+#![crate_name = "style_traits"]
+#![crate_type = "rlib"]
+#![feature(custom_derive)]
+#![feature(plugin)]
+#![plugin(serde_macros)]
+#![deny(unsafe_code)]
+
+extern crate euclid;
+extern crate rustc_serialize;
+extern crate serde;
+extern crate util;
+
+#[macro_use]
+extern crate cssparser;
+
+#[macro_use]
+pub mod values;
+
+pub mod viewport;