Urllib3-future

====================

- Added full asynchronous support using asyncio.
urllib3.future officially support asyncio as his asynchronous scheduler.
The following public classes are immediately available:

``AsyncPoolManager``, ``AsyncHTTPConnectionPool``, ``AsyncHTTPSConnectionPool``, ``AsyncProxyManager``,
``AsyncResolverDescription``.

Finally, bellow functions are also available:

``async_proxy_from_url``, and ``async_connection_from_url``.

Explore the documentation section about async to learn more about this awesome feature with detailed
examples. No extra dependencies are required. We rely exclusively on the standard library.

Async SOCKS proxies are also supported at no additional costs with ``contrib.socks.AsyncSOCKSProxyManager``.

====================

- Improved reliability with PoliceTraffic.borrow with type as indicator when heavily accessed by many threads.

====================

- Fixed an edge case where a simultaneous call to ``get_response()`` without a specific promise could lead to a non-thread safe operation.

====================

- Fixed missed cleanup of unused PoolKey stored in ``PoliceTraffic`` upon a full ``PoolManager``.

====================

- Fixed a compatibility issue with ``boto3`` when trying to send data (got an unexpected keyword argument). 79

====================

- Improved performance and reliability for concurrent streams handled by a single connection.
We relied on a flat array of events generated by the protocol state-machine that unfortunately was not
efficient. urllib3-future now handle the events with a matrix/multi-dimensional array bound to time.
- Fixed a thread safety issue when a single multiplexed connection was used across many threads.
We revised in-depth the logic wrapper around the connection locking to make sure you may
go all-in when using threads in that particular context. In consequence to that:
1) We are, effective immediately, deprecating ``RecentlyUsedContainer``
in favor of our internal ``PoliceTraffic`` that was used in ``PoolManager``.
2) No longer using ``Queue`` to manage the ``Connection`` in ``HTTPConnectionPool``.
If you try to set ``HTTPConnectionPool.QueueCls`` it will raise a deprecation warning.
Starting today, we no longer accept implementation like ``queue.Queue`` because it
cannot fit the need of this complex HTTP client, especially with the multiplexing aspect.
- Increased default pool maxsize for DNS-over-HTTPS from 1 to 10.