o.ymult as an option is not set to Gx.ymult

[bcruhl]

If you pass in the ymult option to a plot, say {ymult: 3}, as well as xmult: 5, it sets the Gx.ymult to use the o.xmult value. See sigplot.js:6754 to see that it is setting Gx.ymult = o.xmult.