title: Resize data points with highcharts
body: <p>We are using <a href="http://www.highcharts.com" rel="noreferrer">highcharts</a> and are trying to customize a chart to look similar to this:
  <img src="https://i.stack.imgur.com/MRrwR.png" alt="enter image description here"></p>
  
  <p>We were able to set colors as documented and also increase the thickness of the lines by using the <code>lineWidth</code> attribute, but can't find a way to customize the data points so they are always circles and larger than the thicker lines. This is what it looks like at this point:
  <img src="https://i.stack.imgur.com/h5jK3.png" alt="enter image description here"></p>
  
  <p>Also, we can't find a way to remove the default gray horizontal lines.</p>
  
  <p>Help! </p>