title: line break for d3 circle title tooltipText
body: <p>I'm using d3's svg, when the tooltipText for a circle title is "line1\nline2", the line is not broken into 2, but just <strong>showing the raw text</strong> "line1\nline2".</p>
  
  <p>tried <a href="https://stackoverflow.com/questions/3340802/add-line-break-within-tooltips">Add line break within tooltips</a> and <a href="https://stackoverflow.com/questions/13049050/can-you-insert-a-line-break-in-text-when-using-d3-js">Can you insert a line break in text when using d3.js?</a>, but not working</p>
  
  <p>Is there a way to have it <strong>show 2 lines</strong> instead of 1 line with raw text? </p>
  
  <p>i.e. <code>\n</code> got interpreted. I assume changing backend response will not help since it's a bug of presentation layer.</p>
  
  <p>Thanks a lot.</p>
  
  <p>Trial-1, replace with "&amp;#013" or "\u000d"</p>
  
  <pre><code>svgContainer.selectAll("g.node").each(function() {
   var node = d3.select(this);
   var tooltipText = node.attr("name"); // tooltipText is "line1\nline2"
   // trying to use entity code, not working. Also tried to replace with "\u000d"
   var tooltipText = node.attr("name").replace("\\n", "&amp;#013"); 
   if (tooltipText) {
     node.select("circle").attr("title", tooltipText);
   }
  </code></pre>
  
  <p>also tried add <code>.attr("data-html", "true")</code> <a href="https://stackoverflow.com/questions/19001766/add-line-break-to-tooltip-in-bootstrap-3/19001875#19001875">Add line break to tooltip in Bootstrap 3</a></p>
  
  <pre><code>svgContainer.selectAll("g.node").each(function() {
   var node = d3.select(this);
   var tooltipText = node.attr("name"); // tooltipText is "line1\nline2"
   // trying to use entity code, not working. Also tried to replace with "\u000d"
   var tooltipText = node.attr("name").replace("\\n", "&amp;#013"); 
   if (tooltipText) {
     node.select("circle")
       .attr("data-html", "true")
       .attr("title", tooltipText);
   }
  </code></pre>