title: How to add a force drag event in D3 and make the node stay where i leave it?
body: <p>i have a D3 api which is showing some relationship between the nodes .I want to apply force.drag() event here where I will drag the node in a position and leave the node and it will stay there.I have a working fiddle here,which is showing the relationship among the nodes.can anyone help me from here to do this event in this api? ..</p>
  
  <p>this is the fiddle</p>
  
  <pre><code>var node = vis
    .selectAll("g.node")
    .data(data.nodes)
    .enter()
    .append("svg:g")
    .attr("class", "node")
    .call(force.drag);
  </code></pre>
  
  <p><a href="http://jsfiddle.net/vuCAx/" rel="nofollow">http://jsfiddle.net/vuCAx/</a></p>
  
  <p>I think the changes should be made here</p>