Added encryption/decryption unit tests discovered security flaw!

Added encryption/decryption unit tests and discovered a security flaw, the
IESEngine being used DOES NOT correctly set the IV properly for block ciphers
instead it initializes the block ciphers each time with the KDF which is even
WORSE as re-using the the IV with OFB completely destroys security.

See: http://en.wikipedia.org/wiki/Block_cipher_modes_of_operation
Merge branch 'master' of github.com:tinfoilhat/tinfoil-sms