szyk-rs

Generic topsort for Rust

Example

```rust use szyk::Node; use szyk;

let result = szyk::sort( &[ Node::new("wooden pickaxe", vec!["planks", "sticks"], "Pickaxe"), Node::new("planks", vec!["wood"], "Planks"), Node::new("sticks", vec!["planks"], "Sticks"), Node::new("wood", vec![], "Wood"), ], "wooden pickaxe", ); assert_eq!(result, Ok(vec!["Wood", "Planks", "Sticks", "Pickaxe"])); ```