anchor.diff:          $("#histogram_sort").tipTip();
           $("#histogram_sort").click(function(event) {
               event.preventDefault(); // Not to scroll to the top
  -
  -            sortPermanently = true;
  +            sortPermanently = !sortPermanently;
  +
  +            $(this).css({
  +                color: !sortPermanently ? "#1974b8" : "gray",
  +                "text-decoration": !sortPermanently ? "none" : "line-through"
  +            });
  +
               drawChart();
           });
   
  
positive.code:                         <option value="4">Show number of altered cases (studies w/o mutation data)</option>
                      </select>
                      |
                      <a href="#" id="histogram_sort" title="Sorts histograms by alteration frequencies in descending order">Sort</a>
                  </div>
                  <div id="chart_div1" style="width: 975px; height: 400px;"></div>
                  <div id="chart_div2" style="width: 975px; height: 400px;"></div>
  
negative.code:               hAxis: {
                  slantedTextAngle: 45
                },
                animation: {
                  duration: 750,
                  easing: 'linear'
            	  },
  	          yAxis: {
  	      	    title: 'Number of cases'
  	          },
                isStacked: true
              };
  
  