[faiss v1.7.1] Add get,set verbose for Index

[ava57r]

facebookresearch/faiss#1790

[Enet4]

Thank you for your contributions to faiss-rs so far, @ava57r. Once these capabilities are given an actual release tag at the Faiss project, please let me know through these PRs, so that they may be reviewed. An eventual release of faiss-rs (0.10.0) is also soft blocked on an upcoming release, as it depends on the changes to CMake in order to build the C API.

[ava57r]

I finished.
You can review it

[Enet4]

This does not compile with the gpu Cargo feature, but should be easy to fix.