Update c3.js and c3.min.js

c3.js

@@ -8251,9 +8251,9 @@
             var widthLimits = [
                 // Left is width, right is number of tick labels to be removed
                 [-Infinity],
-                [200, 10],
-                [300, 5],
-                [450, 2],
+                [320, 10],
+                [400, 5],
+                [475, 2],
                 [Infinity, 1]
             ];
             var divisor;