Add a macro for generating wrapper types

[elichai]

A lot of time you use multiple different UUIDs for different purposes in the same app, in those scenarios you want to wrap the Uuid type with your own, you start with a slim API and slowly it grows and grows for each wrapper type.
if the library could export a macro_rules macro that creates wrapper types with all the API included that could be pretty cool.
(honestly, it is starting to feel like this should be a language feature :) )

Would love to hear other opinions :) (if you're supportive of this I can find some time to draft a PR)

[jacobggman]

This would be also useful for me.

I think this can be implemented with generics.

Example use:

pub struct Team {
    pub name: String,
    pub uuid: TypedUuid<Team>,
}

pub struct Player {
    pub name: String,
    pub uuid: TypedUuid<Player>,
}

fn main() -> io::Result<()> {

    let team = Team { name: "Liverpool".to_string(), uuid: TypedUuid::new() };

    let mut teams_map: HashMap<TypedUuid<Team>, Team> = HashMap::new();
    teams_map.insert(team.uuid, team.clone());

    let team = Team { name: "Chelsea".to_string(), uuid: TypedUuid::new() };

    let player = Player { name: "Sadio Mane".to_string(), uuid: TypedUuid::new() };

    // ERROR: mismatched types expected struct `TypedUuid<Team>` found struct `TypedUuid<Player>`
    teams_map.insert(player.uuid, team);
    
    Ok(())
}

Also maybe if we add this feature like that a macro of creating uuid typed field for spasific struct can be useful.
Example use:

#[with_uuid]
pub struct Team {
    pub name: String,
    //  This is automatic added:  
    // pub uuid: TypedUuid<Team>,
}

I can share how I implemented this if someone would like.

Also, I would like to open PR for this if this feature is welcome :)

[KodrAus]

This is something I do as well, usually via a new-type though without many/any methods on them.

I don't think this is something we need to provide first-class support for in uuid itself, but if anyone wanted to create a library that generates wrapped uuid types for you then I think that would be a useful thing to have.