Version 2.47.2

- Handling of the "result", "in", "in2" attributes in filter
  primitives is slightly stricter now, and spec compliant.  Their
  arguments must be of type CSS custom-ident, so "default", "inherit",
  "initial", and "unset" are disallowed.  Most SVGs should still work
  fine.

- #542 - Fix infinite loop when processing CSS sibling combinators.

- #408 - feImage filters no longer clip their output to integer
  coordinates.

- #504 - Documentation for the Rust crate (available at
  https://gnome.pages.gitlab.gnome.org/librsvg/doc/librsvg/) now has
  API usage examples.

- Debug logs from RSVG_LOG=1 should now be more legible and contain
  better information on invalid CSS.

- Remove link-time workarounds for Rust pre-1.35 (Kleis Auke Wolthuizen).

- Unify internal error types to share the CSS code with gnome-shell.

- Made handling of XML namespaces more spec-compliant.

- Lots of refactoring to start moving away from Cairo internals
  (Paolo Borelli).