Changed to use AES-CBC with HMAC-SHA1, rather than plain Blowfish ECB

Changed to use AES-CBC with HMAC-SHA1, rather than plain Blowfish ECB
for authenticated encryption and associated data ( encrypt then mac )

Server never records the encryption keys now, the url contains the
decryption keys, unless a user passphrase is used.

User passphrases are passed through PBKDF2 for improved entropy.

Duress key provides lorem ipsum text.