Support legend output in PDF QuickPlot

[jng]

The PDF QuickPlot should support the ability for a legend to be included as well.

[jng]

Fixed r2748, r2749, r2750, r2751

[steveg]

In the 2.6 Fusion preview the legend option was added to the QuickPlot widget, but there are some problems when you change the DPI of the plot. As you increase the DPI, the size of the legend decreases. I've attached two quickplot PDFs as examples.

Perhaps on line 253 of (PlotAsPDF.php) is where some of the problem exists:

function PxToIn($px, $dpi) {
        return ($px * 25.4) / $dpi;

Also, in Maestro, I've noticed under the Widget Management, when the DefaultDPI is set, the user is not given the option to change the DPI, but if DefaultDPI is blank then the user can choose the options. I think it would be more appropriate to provide a default DPI to the user, but also give the user the option to change it.

[jng]

Fixed r2798