Add image property for visible objects

[traviskirton]

let C4Image = shape.image

This should take into consideration the bounds of shape line widths.

let C4Image = view.image

This should render all sublayers, taking into the view's masksToBounds property.

[alejandro-isaza]

May be better to do shape.render()

[traviskirton]

yup, the above were just placeholders...

there are options I was planning to consider like:

obj.bitmap()
obj.bitmap(dpi,scale)

also

obj.drawIn(pdfContext)

will have a think on all these and post something I hope is reasonably intelligent..