new graphics engine features

[trevorld]

Introduced in R 4.2

• [ ] affine transformations
• [ ] compositing operators
• [ ] luminance masks
• [ ] stroking and filling paths

Introduced in R 4.3

• [ ] glyphs

In a {vdiffr} issue comment @teunbrand writes:

In addition to pattern support, it would be nice to have support for other newer graphical features as well (clipping paths, masks, compositing/blending, affine transformations, glyphs and fill/stroke paths).

Presumably it would be easier to test these features with {vdiffr} if they were supported by {svglite}