Document complete option in README.

README.md

@@ -137,12 +137,18 @@ jwt.verify(token, cert, { algorithms: ['RS256'] }, function (err, payload) {
 `options`:
 
 * `json`: force JSON.parse on the payload even if the header doesn't contain `"typ":"JWT"`.
+* `complete`: return an object with the decode payload and header.
 
 Example
 
 ```js
 // get the decoded payload ignoring signature, no secretOrPrivateKey needed
 var decoded = jwt.decode(token);
+
+// get the decoded payload and header
+var decoded = jwt.decode(token);
+console.log(decoded.header);
+console.log(decoded.payload)
 ```
 
 ## Errors & Codes