Add test case for deprecated attribute.

Author: luqmana

src/test/compile-fail/lint-deprecated-items.rs

@@ -0,0 +1,10 @@
+#[forbid(deprecated_item)];
+
+type Bar = uint;
+
+#[deprecated = "use Bar instead"]
+type Foo = int;
+
+fn main() {
+    let _x: Foo = 21;
+}