- remove all PHP "_ZMQ_" related dependencies from Pathfinder. PHP´s native Sockets work as replacement

- added status information for "WebSocket" installations to `/setup` page (e.g. active connections, startup time)
- removed "ext-zmq" as required PHP extension
- removed "react/zmq" as required Composer package
- removed "websoftwares/monolog-zmq-handler" as required Composer package

app/main/lib/socket/SocketInterface.php

@@ -0,0 +1,28 @@
+<?php
+/**
+ * Created by PhpStorm.
+ * User: Exodus 4D
+ * Date: 16.02.2019
+ * Time: 11:26
+ */
+
+namespace lib\socket;
+
+
+use React\EventLoop;
+use React\Promise;
+
+interface SocketInterface {
+
+    /**
+     * @return EventLoop\LoopInterface
+     */
+    public function getLoop(): EventLoop\LoopInterface;
+
+    /**
+     * @param string $action
+     * @param null $data
+     * @return Promise\PromiseInterface
+     */
+    public function write(string $action, $data = null) : Promise\PromiseInterface;
+}