title: Possible to set the x values used in OpenPyxl?
body: <p><img src="https://i.stack.imgur.com/xuIOM.png" alt="enter image description here"></p>
  
  <p>I'm trying to achieve the following in openypxl. 
  I want to use the delay times as the values for the xaxis. I can get the proper series added into the chart fine, but am having issues with the delay. The graph is representing my desired output. Is this possible?</p>
  
  <pre><code>chart_object= charts.LineChart()
  x_axis= charts.Reference(overall_stats_sheet, (11,2), (11, 5))
  chart_object.set_categories(x_axis)
  </code></pre>
  
  <p>Continuing this discussion here:
  <a href="https://groups.google.com/forum/#!topic/openpyxl-users/PGL9-9K-Xok" rel="nofollow noreferrer">https://groups.google.com/forum/#!topic/openpyxl-users/PGL9-9K-Xok</a></p>