rustc: Remove ~[T] from the language

The following features have been removed

* box [a, b, c]
* ~[a, b, c]
* box [a, ..N]
* ~[a, ..N]
* ~[T] (as a type)
* deprecated_owned_vector lint

All users of ~[T] should move to using Vec<T> instead.

src/libcore/lib.rs

@@ -130,11 +130,6 @@ pub mod str;
 pub mod tuple;
 pub mod fmt;
 
-// FIXME: this module should not exist. Once owned allocations are no longer a
-//        language type, this module can move outside to the owned allocation
-//        crate.
-mod should_not_exist;
-
 #[doc(hidden)]
 mod core {
     pub use failure;