crossbeam-deque 0.6.3

Concurrent work-stealing deque
Documentation
# Version 0.6.3

- Bump `crossbeam-epoch` to `0.7`.

# Version 0.6.2

- Update `crosbeam-utils` to `0.6`.

# Version 0.6.1

- Change a few `Relaxed` orderings to `Release` in order to fix false positives by tsan.

# Version 0.6.0

- Add `Stealer::steal_many` for batched stealing.
- Change the return type of `pop` to `Pop<T>` so that spinning can be handled manually.

# Version 0.5.2

- Update `crossbeam-utils` to `0.5.0`.

# Version 0.5.1

- Minor optimizations.

# Version 0.5.0

- Add two deque constructors : `fifo()` and `lifo()`.
- Update `rand` to `0.5.3`.
- Rename `Deque` to `Worker`.
- Return `Option<T>` from `Stealer::steal`.
- Remove methods `Deque::len` and `Stealer::len`.
- Remove method `Deque::stealer`.
- Remove method `Deque::steal`.

# Version 0.4.1

- Update `crossbeam-epoch` to `0.5.0`.

# Version 0.4.0

- Update `crossbeam-epoch` to `0.4.2`.
- Update `crossbeam-utils` to `0.4.0`.
- Require minimum Rust version 1.25.

# Version 0.3.1

- Add `Deque::capacity`.
- Add `Deque::min_capacity`.
- Add `Deque::shrink_to_fit`.
- Update `crossbeam-epoch` to `0.3.0`.
- Support Rust 1.20.
- Shrink the buffer in `Deque::push` if necessary.

# Version 0.3.0

- Update `crossbeam-epoch` to `0.4.0`.
- Drop support for Rust 1.13.

# Version 0.2.0

- Update `crossbeam-epoch` to `0.3.0`.
- Support Rust 1.13.

# Version 0.1.1

- Update `crossbeam-epoch` to `0.2.0`.

# Version 0.1.0

- First implementation of the Chase-Lev deque.