[Improvement] Replace fsockopen with stream_socket_client

[mfuehrer82]

The stream extension has a lot more configuration options.

See further:
http://php.net/manual/en/intro.stream.php

[hollodotme]

Seems this will lead to a little BC break as stream_socket_client() expects the remote socket address instead of just host and port which fsockopen() requires.

So I'll change the interface of hollodotme\FastCGI\Interfaces\ConfiguresSocketConnection from:

<?php declare(strict_types=1);

interface ConfiguresSocketConnection
{
	public function getHost() : string;

	public function getPort() : int;

	public function getConnectTimeout() : int;

	public function getReadWriteTimeout() : int;
}

to:

<?php declare(strict_types=1);

interface ConfiguresSocketConnection
{
	public function getSocketAddress() : string;

	public function getConnectTimeout() : int;

	public function getReadWriteTimeout() : int;
}

Furthermore the remote socket address requires a transport protocol which is tcp:// for network sockets and unix:// for unix domain sockets. To make the first parameters of NetworkSocket and UnixDomainSocket constructors consistent, the transport protocol must be omitted in both cases. That means creating a UnixDomainSocket connection must be constructed like this:

<?php declare(strict_types=1);

# Only the socket path must be passed
$connection = new UnixDomainSocket( '/var/run/php/php7.1-fpm.sock' );

Until now it was:

<?php declare(strict_types=1);

$connection = new UnixDomainSocket( 'unix:///var/run/php/php7.1-fpm.sock' );

The transport protocol will be statically added by the both connection classes.