[Libguestfs] Versioning of rust bindings

In the last patch, I let the version of Rust bindings be the same as the version of libguestfs. However, I came to think it is not preferable in terms of the custom of Rust crate versioning. After a version of a crate is published to crates.io, no one can republish the crate with the same version. This means that when there are some mistakes in the rust bindings, after they are fixed, it is required to add the version to publish it. I'm not sure about the versioning of libguestfs, but I believe that it is not preferable that the versioning issue of rust bindings affects the whole versioning of libguestfs. Though it is available to hack SemanticVersioning by using suffixes(as we discussed before), maybe it is not preferable like 1.40.0-ver1. So, I think the versioning of rust bindings should be independent of the one of libguestfs. Do you agree, or not? Regards, Hiroyuki