title: Inner Plot Margin with Default XTS Plot
body: <p>When plotting an XTS object without any custom <code>par</code> attributes, I get a margin <em>within</em> the plot box (or "plot area" going off of <a href="http://research.stowers-institute.org/efg/R/Graphics/Basics/mar-oma/index.htm" rel="nofollow noreferrer">http://research.stowers-institute.org/efg/R/Graphics/Basics/mar-oma/index.htm</a>):</p>
  
  <p><img src="https://i.stack.imgur.com/Owfa1.png" alt="enter image description here">  </p>
  
  <p>(It is hard to see due to white on white, but there is another maybe 20px or so between plot box (the box with the solid black line) and the edge of the image).</p>
  
  <p>How can I adjust the margin within the plot box?</p>