Clippy's `use_self` line ensures that `Self` is used instead of the real
name whenever possible. This makes searching easier and cleans up the
code a bit.
Some basic cleanup of function signatures that took ownership of their
parameters, even though they didn't need ownership. Switching over the
usage of `Arc` to a normal borrow has the added benefit of cleaning up
the code a bit since now a reference can be given instead of having to
clone the values. The other benefit is that a lot of clones aren't
necessary anymore. It's not going to have noticable performance
benefits, but it is still a good thing to have less clones all over the
code.
