Hash160 now outputs a buffer

src/crypto.js

@@ -11,7 +11,7 @@ function hash160(buffer) {
   var step2a = convert.bytesToWordArray(step1)
   var step2b = CryptoJS.RIPEMD160(step2a)
 
-  return convert.wordArrayToBytes(step2b)
+  return new Buffer(convert.wordArrayToBytes(step2b))
 }
 
 function hash256(buffer) {

src/hdwallet.js

@@ -130,7 +130,7 @@ HDWallet.prototype.getIdentifier = function() {
 }
 
 HDWallet.prototype.getFingerprint = function() {
-  return this.getIdentifier().slice(0, 4)
+  return Array.prototype.slice.call(this.getIdentifier(), 0, 4)
 }
 
 HDWallet.prototype.getAddress = function() {