RFC: Integrating rsvg-rs into librsvg

- gnome, librsvg, rust

I have started an RFC to integrate rsvg-rs into librsvg. rsvg-rs is the Rust binding to librsvg. Like the gtk-rs bindings, it gets generated from a pre-built GIR file.

It would be nice for librsvg to provide the Rust binding by itself, so that librsvg's own internal tools can be implemented in Rust — currently all the tests are done in C, as are the rsvg-convert(1) and rsvg-view-3(1) programs.

There are some implications for how rsvg-rs would get built then. For librsvg's internal consumption, the binding can be built from the Rsvg-2.0.gir file that gets built out of the main librsvg.so. But for public consumption of rsvg-rs, when it is being used as a normal crate and built by Cargo, that Rsvg-2.0.gir needs to be already built and available: it wouldn't be appropriate for Cargo to build librsvg and the .gir file itself.

If this sort of thing interests you, take a look at the RFC!