`getXValue` returns the index when x is specifically 0, because it's falsey. Fixed that by checking the specific case.
I have not updated c3.min.js.

Sometimes the data provided can't be used for <code>transformForArcLabel</code> (a stacked area chart where registered items came back as neither connected or disconnected. http://jsfiddle.net/U5g3h/). I find that the <code>startAngle</code> and <code>endAngle</code> values arrive as <code>NaN</code>. To fix this I am checking before assigning <code>x</code> and <code>y</code>.

add cusom name support

Good catch. <code>init()</code> is now only defining the <code>text</code> tag in the main chart. I've moved the setting of the <code>x</code> and <code>y</code> into <code>redraw()</code> along with the label text. <code>x</code> and <code>y</code> are using <code>width</code> and <code>height</code> instead of calculating <code>(getCurrentWidth() - margin.left - margin.right)</code> as before. Indentation corrected as well, so Travis CI shouldn't error out on that either.