Use translate instead of dx for compatibility with Batik

src/axis.js

@@ -323,11 +323,13 @@ c3_chart_internal_fn.rotateTickText = function (axis, transition, rotate) {
                 return 'middle';
             }
         });
+
+    // Here we use translate for <text> instead of dx for <tspan>
+    // because Batik rasterizer ignores dx attribute
+    var yOffset = -this.xForRotatedTickText(rotate);
     transition.selectAll('.tick text')
         .attr("y", this.yForRotatedTickText(rotate))
-        .attr("transform", "rotate(" + rotate + ")")
-      .selectAll('tspan')
-        .attr('dx', this.xForRotatedTickText(rotate));
+        .attr("transform", "translate(0 "+ yOffset +") rotate(" + rotate + ")");
 };
 
 c3_chart_internal_fn.getMaxTickWidth = function (id) {