Lines Demo renders as planes

[kephale]

lol

To reproduce:

• Run LinesDemo in sciview

Tagging @skalarproduktraum @moreApi

[skalarproduktraum]

This is art #wontfix 😂

[kephale]

"You just called it LinesDemo because you're in 1D flatland! Wake up"

[moreApi]

I have no idea. But @PowerOfNames is working on lines.

[kephale]

@skalarproduktraum this still seems to be present.

[kephale]

The upstream scenery issue was closed because this is a macos issue. There isn't a fix, so the idea is:

• remove LineDemo because Line3DDemo does the job anyway
• update SciView.addLine to use cylinders instead of scenery Lines