allow changing orient of axes

[jspeis]

Bars appear to overlap axis when using a right orientation for the y-axis

see https://jsfiddle.net/huzcorjf/
using Chrome / Mac OS

[davelandry]

ahhh I see the issue here. we never expected someone to change the actual orient of the axes, but rather just use the x2 and y2 secondary axes. In the meantime, check out this somewhat of a hack: https://jsfiddle.net/dfxcnrpg/