Remove mention of Dequeue in collections docs.

  https://botbot.me/mozilla/rust/2014-12-07/?msg=27003846&page=20

Author: steveklabnik

src/libcollections/dlist.rs

@@ -11,9 +11,6 @@
 //! A doubly-linked list with owned nodes.
 //!
 //! The `DList` allows pushing and popping elements at either end.
-//!
-//! `DList` implements the trait `Deque`. It should be imported with
-//! `use collections::Deque`.
 
 // DList is constructed like a singly-linked list over the field `next`.
 // including the last link being None; each Node owns its `next` field.

src/libcollections/ring_buf.rs

@@ -11,7 +11,6 @@
 //! This crate implements a double-ended queue with `O(1)` amortized inserts and removals from both
 //! 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.
-//! Its interface `Deque` is defined in `collections`.
 
 use core::prelude::*;
 
@@ -35,7 +34,7 @@ static MINIMUM_CAPACITY: uint = 2u;
 // FIXME(conventions): implement shrink_to_fit. Awkward with the current design, but it should
 // be scrapped anyway. Defer to rewrite?
 
-/// `RingBuf` is a circular buffer that implements `Deque`.
+/// `RingBuf` is a circular buffer.
 pub struct RingBuf<T> {
     // tail and head are pointers into the buffer. Tail always points
     // to the first element that could be read, Head always points