Add examples in all supported languages

[PhilipMetzger]

As far as I can see fbthrift supports all major languages which are used at Meta (Hack, Cpp, Rust, Python and Java ¹) but the examples directory only contains a simple Python and Cpp client/server example.

Hopefully this is just a port of internal examples.

Thanks.

Footnotes

1. Taken from https://engineering.fb.com/2022/07/27/developer-tools/programming-languages-endorsed-for-server-side-use-at-meta/ ↩