Stabilize collection modules

The earlier collections stabilization did not cover the modules
themselves. This commit marks as stable those modules whose types have
been stabilized.

src/libcollections/binary_heap.rs

@@ -148,6 +148,7 @@
 //! ```
 
 #![allow(missing_docs)]
+#![stable]
 
 use core::prelude::*;
 

src/libcollections/dlist.rs

@@ -19,6 +19,8 @@
 // Backlinks over DList::prev are raw pointers that form a full chain in
 // the reverse direction.
 
+#![stable]
+
 use core::prelude::*;
 
 use alloc::boxed::Box;

src/libcollections/lib.rs

@@ -65,19 +65,23 @@ pub mod string;
 pub mod vec;
 pub mod vec_map;
 
+#[stable]
 pub mod bitv {
     pub use bit::{Bitv, Iter};
 }
 
+#[stable]
 pub mod bitv_set {
     pub use bit::{BitvSet, Union, Intersection, Difference, SymmetricDifference};
     pub use bit::SetIter as Iter;
 }
 
+#[stable]
 pub mod btree_map {
     pub use btree::map::*;
 }
 
+#[stable]
 pub mod btree_set {
     pub use btree::set::*;
 }

src/libcollections/ring_buf.rs

@@ -12,6 +12,8 @@
 //! ends of the container. It also has `O(1)` indexing like a vector. The contained elements are
 //! not required to be copyable, and the queue will be sendable if the contained type is sendable.
 
+#![stable]
+
 use core::prelude::*;
 
 use core::cmp::Ordering;

src/libstd/collections/mod.rs

@@ -309,7 +309,7 @@
 //! }
 //! ```
 
-#![experimental]
+#![stable]
 
 pub use core_collections::{BinaryHeap, Bitv, BitvSet, BTreeMap, BTreeSet};
 pub use core_collections::{DList, RingBuf, VecMap};
@@ -322,11 +322,13 @@ pub use self::hash_set::HashSet;
 
 mod hash;
 
+#[stable]
 pub mod hash_map {
     //! A hashmap
     pub use super::hash::map::*;
 }
 
+#[stable]
 pub mod hash_set {
     //! A hashset
     pub use super::hash::set::*;