By looking at the code, it seems that it was a goal to make the sudo
wrapper path configurable through the Vagrantfile, but it wasn't
effective and didn't make much sense (that kind of config is a per-host
config, not a per-guest one).
This caused the cause to be needlessly complex by giving the Provider
the responsibility of instanciating the wrapper. This commit gets rid of
that.
I didn't get rid of `sudo_wrapper` injection in `Driver` and
`Driver::CLI` constructors because they're needed for tests. I'm not
ready to tackle this yet.
