Derive Macro VersionFamily 

#[derive(VersionFamily)]
{
    // Attributes available to this derive:
    #[thisversion]
}

Connects a chronological enum through caller-provided From or TryFrom conversions. Its latest schema defines the model and error types.

Generates From<Schema> for every family variant and model conversion implementations. Infallible migrations and model conversion are the default. Add #[thisversion(fallible)] to the enum when a migration or the latest schema’s model conversion can fail; migration errors must convert into its model error.