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);

e.addListener('data', function(chunk) {
  d.write(chunk);
});
e.addListener('end', function() {
  d.end();
});
d.addListener('data', function(chunk) {
  if (chunk.length > 0)
    console.log('data: ' + chunk);
});

e.write("Hello world", 'binary');
e.end();