Simplify definitions and impls of Vertex-containing types

[nvzqz]

By not requiring so many bounds on Vertex at type definition time, it becomes easier to modify this code.

[obi1kenobi]

Thanks! Although I am worried about worse compile errors now that it's possible for someone to pass a Vertex that is not Debug or Clone, and for some impls to not be available on DataContext as a result.

[nvzqz]

I kept the trait bounds on DataContext::new, so that shouldn't be an issue 🙂

trustfall/trustfall_core/src/interpreter/mod.rs

Lines 183 to 195 in 7b36bfa

	impl<Vertex: Clone + Debug> DataContext<Vertex> {
	pub fn new(vertex: Option<Vertex>) -> DataContext<Vertex> {
	DataContext {
	active_vertex: vertex,
	piggyback: None,
	vertices: Default::default(),
	values: Default::default(),
	suspended_vertices: Default::default(),
	folded_contexts: Default::default(),
	folded_values: Default::default(),
	imported_tags: Default::default(),
	}
	}

[obi1kenobi]

Nice!