Feature / BC break: Pass connector into Client instead of loop, remove unneeded deps (#49 by @clue)

// old (connector is create implicitly)
$client = new Client('127.0.0.1', $loop);

// old (connector can optionally be passed)
$client = new Client('127.0.0.1', $loop, $connector);

// new (connector is now mandatory)
$connector = new React\SocketClient\TcpConnector($loop);
$client = new Client('127.0.0.1', $connector);

Feature / BC break: Client now implements ConnectorInterface, remove Connector adapter (#47 by @clue)

// old (explicit connector functions as an adapter)
$connector = $client->createConnector();
$promise = $connector->create('google.com', 80);

// new (client can be used as connector right away)
$promise = $client->create('google.com', 80);

Feature / BC break: Remove createSecureConnector(), use SecureConnector instead (#47 by @clue)

// old (tight coupling and hidden dependency)
$tls = $client->createSecureConnector();
$promise = $tls->create('google.com', 443);

// new (more explicit, loose coupling)
$tls = new React\SocketClient\SecureConnector($client, $loop);
$promise = $tls->create('google.com', 443);

Feature / BC break: Remove setResolveLocal() and local DNS resolution and default to remote DNS resolution, use DnsConnector instead (#44 by @clue)

// old (implicitly defaults to true, can be disabled)
$client->setResolveLocal(false);
$tcp = $client->createConnector();
$promise = $tcp->create('google.com', 80);

// new (always disabled, can be re-enabled like this)
$factory = new React\Dns\Resolver\Factory();
$resolver = $factory->createCached('8.8.8.8', $loop);
$tcp = new React\SocketClient\DnsConnector($client, $resolver);
$promise = $tcp->create('google.com', 80);

Feature / BC break: Remove setTimeout(), use TimeoutConnector instead (#45 by @clue)

// old (timeout only applies to TCP/IP connection)
$client = new Client('127.0.0.1', …);
$client->setTimeout(3.0);
$tcp = $client->createConnector();
$promise = $tcp->create('google.com', 80);

// new (timeout can be added to any layer)
$client = new Client('127.0.0.1', …);
$tcp = new React\SocketClient\TimeoutConnector($client, 3.0, $loop);
$promise = $tcp->create('google.com', 80);

Feature / BC break: Remove setProtocolVersion() and setAuth() mutators, only support SOCKS URI for protocol version and authentication (immutable API) (#46 by @clue)

// old (state can be mutated after instantiation)
$client = new Client('127.0.0.1', …);
$client->setProtocolVersion('5');
$client->setAuth('user', 'pass');

// new (immutable after construction, already supported as of v0.5.2 - now mandatory)
$client = new Client('socks5://user:pass@127.0.0.1', …);