Skia-pathops

Testing automatic deployment

Also build Python 3.9 wheels.

Avoid including the private SkGeometry.h header in pathops/_skia/core.pxd.
Reimplement the previously imported SkConic::computeQuadPOW2 method in Cython (33, 34).

Added support for decomposing components when drawing onto a Path using FontTools pen interface. A glyphSet option (None by default) is added to Path.getPen method, and to PathPen constructor.
This should be a mapping of drawable glyphs keyed by glyph name.

No longer silently ignore components, but raise an error if the glyphSet parameter (needed to resolve component references) is not provided when getting or constructing the PathPen (29, 32).

Added clockwise=False option to control outermost contour direction (30, 31).

Path.stroke no longer calls Path.convertConicsToQuads itself.
Clients can call that directly (passing a desired tolerance) if they don't want to deal with conics that may be introduced as result of the stroking operation.