Feature / BC break: Use connect($uri) instead of create($host, $port)
and resolve with a ConnectionInterface instead of Stream
and expose remote and local addresses through this interface
and remove superfluous and undocumented ConnectionException.
(#74, #82 and #84 by @clue)

// old
$connector->create('google.com', 80)->then(function (Stream $conn) {
    echo 'Connected' . PHP_EOL;
    $conn->write("GET / HTTP/1.0\r\n\r\n");
});

// new
$connector->connect('google.com:80')->then(function (ConnectionInterface $conn) {
    echo 'Connected to ' . $conn->getRemoteAddress() . PHP_EOL;
    $conn->write("GET / HTTP/1.0\r\n\r\n");
});

Note that both the old Stream and the new ConnectionInterface implement
the same underlying DuplexStreamInterface, so their streaming behavior is
actually equivalent.
In order to upgrade, simply use the new typehints.
Existing stream handlers should continue to work unchanged.

Feature / BC break: All connectors now MUST offer cancellation support.
You can now rely on getting a rejected promise when calling cancel() on a
pending connection attempt.
(#79 by @clue)

// old: promise resolution not enforced and thus unreliable
$promise = $connector->create($host, $port);
$promise->cancel();
$promise->then(/* MAY still be called */, /* SHOULD be called */);

// new: rejecting after cancellation is mandatory
$promise = $connector->connect($uri);
$promise->cancel();
$promise->then(/* MUST NOT be called */, /* MUST be called */);

Note that this behavior is only mandatory for pending connection attempts.
Once the promise is settled (resolved), calling cancel() will have no effect.

BC break: All connector classes are now marked final
and you can no longer extend them
(which was never documented or recommended anyway).
Please use composition instead of extension.
(#85 by @clue)