Improve `Debug` derives

[Jasper-Bekkers]

Right now, a bunch of structs derive from Debug which is quite nice in general, however a lot of them have a reference to the parent document as one of their first elements causing a lot of commandline spew when I call dbg!() on them.

I'd love to see custom Debug implementations for all structs that start with a document: &'a Document. I've thought of suggesting simply moving the borrow to the last member of the struct, but that'll still end up in a lot of useless information outputted.

[alteous]

I see your point and I agree, the debug output could be more conservative.

[felipellrocha]

Any progress on this? This would be a fantastic improvement