Derive Macro Transactable 

#[derive(Transactable)]
{
    // Attributes available to this derive:
    #[etch]
}

Derive Transactable for a struct with #[etch(collection = N)] fields.

Generates:

• A transaction struct ({Name}Tx) with Collection fields
• An overlay struct ({Name}Overlay) with Overlay fields
• The full Transactable trait implementation