[Libguestfs] Welcome Hiroyuki Katsura as Google Summer of Code 2019 student

Dear libguestfs developers and users, it is my pleasure to welcome Hiroyuki Katsura as Google Summer of Code 2019 student for libguestfs! He will work on adding Rust bindings, to allow using libguestfs in Rust applications. You can read the project submission here: https://summerofcode.withgoogle.com/projects/#6730007286644736 I'm the main mentor of this project, with Rich Jones, and Martin Kletzander as co-mentors. Hiroyuki: feel free to ask away about anything, from design questions to doubts about the existing code, etc. Welcome again, Hiroyuki! -- Pino Toscano