Properly align Label in a FormItem

[AlbinoGeek]

Is your feature request related to a problem? Please describe:

When you have a Label and an Entry in a FormItem, the Label is missing top-padding required to bring its text in line with the Entry's text.

Example:

	updatePeriod := widget.NewEntry()
	updatePeriod.SetText(getUpdateDuration().String())
	// ...
	window.SetContent(widget.NewVBox(
		widget.NewGroup("Updates",
			widget.NewForm(
				widget.NewFormItem("Time Between Checks", updatePeriod),
			),
		),
	))
	// ...

Is it possible to construct a solution with the existing API?

Yes.

Describe the solution you'd like to see:

Add 3-5 pixels of top padding to Label inside a FormItem

The baseline of the two pieces of text should match horizontally.

[stuartmscott]

This may not be specific to widget.Form, instead we may want canvas.Text to be drawn in the vertical center of the texture (currently d.Dot = freetype.Pt(0, height-face.Metrics().Descent.Ceil()))

[AlbinoGeek]

I think that may even fix the issue with Button and Label alignment if that were the case.

[andydotxyz]

On develop for testing :)