Modernize the Rust code, upgrade the dependencies to avoid including security vulnerabilities and remove warnings

This MR is pretty straightforward, it simply update the code for the newer rust compiler, fixing some warnings, Upgrades the dependencies because there was a dependency with a vulnerability and fix the build with incompatible new dependencies Some more advanced clippy warnings are also fixed

no functionality is changed and the testsuite pass

I hope you can consider merging and make a new release of the crate, I am using this crate in one of my projects

Thanks

Marco