title: inline style stroke-width for axis makes bold tick labels
body: <p>I do not use css since I want to save and process the created SVG visualisation files. This means I need to use inline styles. So far I experienced d3 as flawless so most likely I did do something wrong. </p>
  
  <p>I am expecting {'stroke-width': '3px'} to make thick axis lines. But it makes bold axis labels. I expected the text to be controlled with font related styles like {'font-style': 'normal'}.</p>
  
  <p>Whats wrong with how I use 'stroke-width'? I tested this in both Chrome and Firefox.</p>
  
  <p>here is my code:</p>
  
  <pre><code>&lt;script&gt;
      var margin = {top: 20, right: 10, bottom: 20, left: 40};
      var width = 960 - margin.left - margin.right;
      var height = 100 - margin.top - margin.bottom;
  
      var x = d3.scale.linear().range([0, width]);
      var y = d3.scale.linear().range([0, height]);
      var xAxis = d3.svg.axis().scale(x).orient("bottom");
            // .tickFormat(d3.time.format("%H:%M"));
      var yAxis = d3.svg.axis().scale(y).orient("left").ticks(height/10);
  
      var svg = d3.select("svg");
      var vis = svg.append("g")
          .attr("transform", "translate(" + margin.left + "," + margin.top + ")")
          .style({'font-size': '10px', 'font-family': 'sans-serif',
              'font-style': 'normal', 'font-variant': 'normal', 
              'font-weight': 'normal'});
  
      var redraw = function(selection, data, style) {
          selection.selectAll(".bar")
              .data(data)
            .enter().append("rect")
              .attr('class', "bar")
              .attr("x", function(d) { return x(d[0]) - .5; })
              .attr("y", function(d) { return y(d[1]); })
              .attr("width", 5)
              .attr("height", function(d) { return height - y(d[1]);  })
              .style(style);
  
          vis.select(".x.axis").call(xAxis);
          vis.select(".y.axis").call(yAxis);
      };
  
      svg.attr("width", width + margin.left + margin.right)
          .attr("height", height + margin.top + margin.bottom);
  
      vis.append("g")
        .attr("class", "x axis")
        .attr("transform", "translate(0," + height + ")")
        .style({ 'stroke': 'Black', 'fill': 'none', 'stroke-width': '3px'})
        .call(xAxis);
  
      vis.append("g")
        .attr("class", "y axis")
        .style({ 'stroke': 'Black', 'fill': 'none', 'stroke-width': '3px'})
        .call(yAxis);
  
      // now we draw the first barchart (we do not know about the 2nd one yet)
      var data1 = [[2,0.5], [4,0.8], [6,0.6], [8,0.7], [12,0.8]];
      x.domain([0, 13]);
      y.domain([0.9, 0]);
  
      vis.append("g")
        .attr("class", "bar1");
  
      vis.select(".bar1")
        .call(redraw, data1, {'fill': 'Red', 'stroke': 'Black'});
  &lt;/script&gt;
  </code></pre>