Stream object for crypto.

Example Usage:

var DecryptStream = require('./lib/cryptostream.js').DecryptStream;
var EncryptStream = require('./lib/cryptostream.js').EncryptStream;

var key = 'nodecryptostream';

var e = new EncryptStream(key);
var d = new DecryptStream(key);

fs.createReadStream(__filename).pipe(e).pipe(d).pipe(process.stdout, {end: false})

EncryptStream/DecryptStream (opts)

opts may be a the key (string) or a object. If opts is an object it must have properties for key and algorithm, and may have properties inputEncoding and outputEncoding

also see http://nodejs.org/api/crypto.html#crypto_crypto_createcipher_algorithm_password