Peginator macro

Proc-macro support for peginator. Please find doucmentation and other goodies on the main project.

Usage: ```rust use peginator_macro::peginate; use peginator::PegParser;

peginate!(" @export PizzaRule = 'Pizza' 'with' toppings:Topping {',' toppings:Topping} ['and' toppings:Topping] ; @string Topping = 'sausage' | 'pineapple' | 'bacon' | 'cheese'; ");

fn main() { let result = PizzaRule::parse("Pizza with sausage, bacon and cheese").unwrap(); println!("{:?}", result.toppings); } ```