title: Is an NVD3 Line Plot with Markers Possible?
body: <p>I'm making an NVD3 line plot that will have significantly improved clarity if I can get markers to show for each data point instead of just the line itself. Unfortunately, I haven't been able to find an easy way to do this with NVD3 yet. I also considered using a scatter plot, but I couldn't figure out how to show connecting lines between the points. A third option I considered was to overlay a line and scatter plot, but this would show each series twice in the legend and may cause other unnecessary visual complications.</p>
  
  <p>Is there a way to elegantly pull this off yet? Sample code of my formatting technique is listed below, but the 'size' and 'shape' attributes in test_data have no effect on the line plot with the current code.</p>
  
  <pre><code>test_data = [ {     key: 'series1',
              values: [
                  { x: 1, y: 2.33, size:5, shape:"circle" },
                  { x: 2, y: 2.34, size:5, shape:"circle" },
                  { x: 3, y: 2.03, size:5, shape:"circle" },
          ] } ];
  
  
  nv.addGraph(function() {
    var test_chart = nv.models.lineChart();
    test_chart.xAxis.axisLabel('Sample Number');
    test_chart.yAxis
          .axisLabel('Voltage (V)')
          .tickFormat(d3.format('.02f'));
  
    d3.select('#test_plot')
        .datum(test_data)
      .transition().duration(500)
        .call(test_chart);
  
    nv.utils.windowResize(test_chart.update);
    return test_chart;
  });
  </code></pre>