collections of useful macros

example

use useful_macro::*;
//get argument and into Vec<String>
let arg = args!();
println!("{:?}",arg);

//get input and into String
let s = input!();
println!("{:?}",s);

//power of two f64 number
let p = powf!(2.,2.);
println!("{:?}",p);

//split a:&str by b:&str and collect into Vec<String>  
let s = split_to_vec!("aa.bb",".");
println!("{:?}",s);