Angled labels on x-axis can cause start of y-axis grid lines to be rendered incorrectly (v2.0)

[tomduncalf]

With angled tick labels on the x-axis, the start of the y-axis grid lines gets offset, which looks incorrect as it introduces a gap before the chart starts.

Actual result:

(start of y-axis grid lines is offset, leaving blank space before the chart)

Expected result:

(start of y-axis grid lines aligns with first tick of x-axis)

Test case: http://jsbin.com/katihageca/1/edit?html,js,output

Thanks

[etimberg]

One option is to set the maxRotation to 0 on the x axis, but it's only slightly better: http://jsbin.com/yifuxuqura/1/edit?html,js,output