The cbindgen generated header should not include rust.h as
rust.h already includes the generated binding.
Fixup C source code that only pulled the generated include, it
should instead pull in "rust.h" which includes the generated
binding plus other misc. stuff.
JsonBuilder is a Rust module for creating JSON output. Unlike
Jansson, the final JSON string is built up as items are added,
instead of building up an object tree and rendering it when
done.
The idea is to create a more efficient JSON serializer instead
of a flexible one.