number_easing

number easing functions

```rust extern crate number_easing;

use numbereasing::{inoutcubic, inout_quad};

fn main() {

assert_eq!(in_out_cubic(0, 100, 0), 0);
assert_eq!(in_out_cubic(0, 100, 0.25), 6);
assert_eq!(in_out_cubic(0, 100, 0.5), 50);
assert_eq!(in_out_cubic(0, 100, 0.75), 93);
assert_eq!(in_out_cubic(0, 100, 1.0), 100);

assert_eq!(in_out_quad(0, 100, 0), 0);
assert_eq!(in_out_quad(0, 100, 0.25), 12);
assert_eq!(in_out_quad(0, 100, 0.5), 50);
assert_eq!(in_out_quad(0, 100, 0.75), 87);
assert_eq!(in_out_quad(0, 100, 1.0), 100);

} ```