IOTA Identity - Diff === This module implements a [`Diff`](crate::Diff) trait. This gives data structures the ability to compare themselves to another data structure of the same type over time. The library pairs off with [`identity_diff_derive`], which implements a derive macro for the [`Diff`](crate::Diff) Trait. Types supported include `HashMap`, `Option`, `String`, `serde_json::Value`, `Vec` and primitives such as `i8`/`u8` up to `usize` and `isize`, as well as the unit type `()`, `bool`, and `char` types. Structs and Enums are supported via [`identity_diff_derive`] and can be composed of any number of these types.