Cleaned up some clippy warnings.

Clippy is a collection of linters for rust.

Most of the changes are just formatting improvements. I setup Clippy to ignore the parse_transform module since it's autogenerated, but you might want to uncommenct this to check out the warnings it returns.

There still some warnings left. Mainly:

• 10 needless_pass_by_value, They are mainly on functions that take foo: Rc<bar> as argument, or Enums so we maybe could ignore it too.
• 4 float_cmp warnings.

I've allowed/skipped the following linters:

• clone_on_ref_ptr, since there many Rc<_> values.
• not_unsafe_ptr_arg_deref since there's safe API wrapper i think.
• too_many_arguments

In every commit message there are links to the warnings it solves.