lint: add lint for use of a ~[T].

This is useless at the moment (since pretty much every crate uses
`~[]`), but should help avoid regressions once completely removed from a
crate.

src/librustdoc/lib.rs

@@ -14,6 +14,7 @@
 #[crate_type = "dylib"];
 #[crate_type = "rlib"];
 
+#[allow(deprecated_owned_vector)];
 #[feature(globs, struct_variant, managed_boxes, macro_rules)];
 
 extern crate syntax;