While this was a workaround for a docs.rs issue (Px/Lp are not
linked), I decided having the shorter import path would look better in
the examples.
It probably wasn't necessary to update all of the references in the
internal code, but I decided it was worth the consistency.
- Blur no longer expands the shadow geometry, but instead is clamped to
avoid overlapping drawing calls.
- Overlay now handles hit tests correctly with regards to the original
relative widget.
- Align was using an Into conversion that wasn't actually correct,
causing the contents to not actually get aligned in some situations.
Rather than clip or cause shadows to be weirdly shaped, the shape is
adjusted if the blur radius is too large for the given geometry. This
ensures the shadows always draw correctly, but it also forces shadows to
render their full blur + spread gradients.
