title: Legends for line charts in Chart.js
body: <p>I'd like to customize a legend for line data so that the legend graphic is a line (styled like the actually data line) rather than a box.</p>
  
  <p>As far as I can tell <a href="https://github.com/chartjs/Chart.js/blob/0dccc85e3a0f6a9e2fa2cb6e4c39533dcbc653d5/src/core/core.legend.js" rel="noreferrer">from the source</a>, the graphic can be a point or a box, and the height of the box is fixed to the font size.  The 'generateLabels' option does not seem to allow for extending around these contraints.</p>
  
  <p>Version 2.2.1.</p>
  
  <p>Thanks for any help.</p>