added aspnetcore package and adapted sample app

Tests/MQTTnet.TestApp.AspNetCore2/wwwroot/Index.html

@@ -0,0 +1,23 @@
+<!DOCTYPE html>
+<html>
+<head>
+    <meta charset="utf-8" />
+    <title>MQTT test</title>
+</head>
+<body>
+<script src="node_modules/systemjs/dist/system.js"></script>
+<script>
+    System.config({
+        packages: {
+            '': {
+                defaultExtension: 'js'
+            }
+        },
+        map: {
+            mqtt: 'node_modules/mqtt/dist/mqtt.min'
+        }
+    });
+    System.import('app/app');
+</script>
+</body>
+</html>

Tests/MQTTnet.TestApp.AspNetCore2/wwwroot/app/app.ts

@@ -0,0 +1,16 @@
+import { connect } from "mqtt";
+
+var client = connect('ws://' + location.host + '/mqtt',
+    {
+        clientId: "client1",
+    });
+
+client.on('connect', () => {
+    client.subscribe('presence');
+    client.publish('presence', 'Hello mqtt');
+});
+
+client.on('message', (topic, message) => {
+    // message is Buffer
+    console.log(message.toString());
+})