`Write-SVG` should `-Decorate` (automatically by element name)

[StartAutomating]

Write-SVG currently marks all output as an SVG.Element, which is a fine starting point.

However, it's not quite enough to be able to assist in all scenarios.

Therefore, Write-SVG should provide a -Decorate parameter, which will allow custom typename decoration of the outputted object.

If this parameter is not present, each object should also be decorated with its element name (i.e. SVG.Path)