the console in improve readability.
</p>

<div id="mynetwork"></div>
<pre id="eventSpan"></pre>

<script type="text/javascript">
    // create an array with nodes
    var nodes = new vis.DataSet([
        {id: 1, label: 'Node 1', title: 'I have a popup!'},
        {id: 2, label: 'Node 2', title: 'I have a popup!'},
        {id: 3, label: 'Node 3', title: 'I have a popup!'},
        {id: 4, label: 'Node 4', title: 'I have a popup!'},
        {id: 5, label: 'Node 5', title: 'I have a popup!'}
    ]);

    // 