Introduction - If you have any usage issues, please Google them yourself
* Corrected KeeLoq Encryption and Decryption functions by Ruptor.
* Use at your own risk! This source is not copyrighted.
* Encoder encrypts an all-0 block, decoder decrypts it.
* KeeLoq cipher encrypts 32-bit blocks with 64-bit keys.
* Key is XORed with a 32-bit IV incremented on each use.
* See http://www.keeloq.boom.ru/decryption.pdf for more details.
* KeeLoq algorithm itself is not patented.