Plot2DCanvas is missing a function

```
What steps will reproduce the problem?
Use Plot2DCanvas insted of PlotPanel.

I was using PlotPanel with the method:
    addLinePlot(String, double[], double[])

When I changed to Plot2DCanvas it gave me a compilation error.
I Guess Plot2DCanvas should also have that method.


```

Original issue reported on code.google.com by `maca...@gmail.com` on 21 Mar 2010 at 4:34
