Clean up IGE example

//! # Examples

//!

//! ```rust

//! # extern crate openssl;

//! extern crate hex;

//! use openssl::aes::{AesKey, KeyError, aes_ige};

//! use openssl::aes::{AesKey, aes_ige};

//! use openssl::symm::Mode;

//! use hex::FromHex;

//!

//! fn decrypt() -> Result<(), KeyError> {

//!   let raw_key = "000102030405060708090A0B0C0D0E0F";

//!   let hex_cipher = "12345678901234561234567890123456";

//!   let randomness = "000102030405060708090A0B0C0D0E0F101112131415161718191A1B1C1D1E1F";

//!   if let (Ok(key_as_u8), Ok(cipher_as_u8), Ok(mut iv_as_u8)) =

//!       (Vec::from_hex(raw_key), Vec::from_hex(hex_cipher), Vec::from_hex(randomness)) {

//!     let key = AesKey::new_encrypt(&key_as_u8)?;

//!     let mut output = vec![0u8; cipher_as_u8.len()];

//!     aes_ige(&cipher_as_u8, &mut output, &key, &mut iv_as_u8, Mode::Encrypt);

//!     assert_eq!(hex::encode(output), "a6ad974d5cea1d36d2f367980907ed32");

//!   }

//!   Ok(())

//! }

//! let key = b"\x00\x01\x02\x03\x04\x05\x06\x07\x08\x09\x0A\x0B\x0C\x0D\x0E\x0F";

//! let plaintext = b"\x12\x34\x56\x78\x90\x12\x34\x56\x12\x34\x56\x78\x90\x12\x34\x56";

//! let mut iv = *b"\x00\x01\x02\x03\x04\x05\x06\x07\x08\x09\x0A\x0B\x0C\x0D\x0E\x0F\

//!                 \x10\x11\x12\x13\x14\x15\x16\x17\x18\x19\x1A\x1B\x1C\x1D\x1E\x1F";

//!

//! # fn main() {

//! #   decrypt();

//! # }

//!  let key = AesKey::new_encrypt(key).unwrap();

//!  let mut output = [0u8; 16];

//!  aes_ige(plaintext, &mut output, &key, &mut iv, Mode::Encrypt);

//!  assert_eq!(output, *b"\xa6\xad\x97\x4d\x5c\xea\x1d\x36\xd2\xf3\x67\x98\x09\x07\xed\x32");

use ffi;

use std::mem;

use libc::c_int;

use std::mem;

use symm::Mode;

mod test {

    use hex::FromHex;

    use symm::Mode;

    use super::*;

    use symm::Mode;

    // From https://www.mgp25.com/AESIGE/

    #[test]