Add documentation for two factor authentication

* added info in README on 2fa
* fixed typo in README
* added example for 2fa

Author: HerrSubset

README.md

@@ -32,7 +32,7 @@ You can also provide your user and pass via environment variables:
 
 ```javascript
 // run as:
-// DEGIRO_USER=johndow DEGIRO_PASS=1234 node app.js
+// DEGIRO_USER=johndoe DEGIRO_PASS=1234 node app.js
 
 const DeGiro = require('degiro');
 // now you don't need to provide your credentials
@@ -48,6 +48,15 @@ degiro.login().then(session => console.log(session));
 // prints session info (session id and account number)
 ```
 
+Two factor authentication is also supported. Pass the 2fa token through javascript or as an environment variable.
+
+```javascript
+const DeGiro = require('degiro');
+// alternatively run as:
+// DEGIRO_USER=johndoe DEGIRO_PASS=1234 DEGIRO_ONE_TIME_PASS=123456 node app.js
+const degiro = DeGiro.create({username: 'johndoe', password: '1234', oneTimePassword: '123456'});
+```
+
 You can reuse your sessions if you provide the id and account number via environment variables (`DEGIRO_SID`
 and `DEGIRO_ACCOUNT`), direct assignment or constructor parameters.
 

examples/two-factor-login.js

@@ -0,0 +1,16 @@
+const DeGiro = require('..');
+
+// Set your username, password and oneTimePassword (google
+// authenticator token) below or run from terminal as:
+// DEGIRO_USER=username DEGIRO_PASS=password DEGIRO_ONE_TIME_PASS=token node examples/two-factor-login.js
+
+ const degiro = DeGiro.create({
+   //     username: 'john',
+   //     password: 'password',
+   //     oneTimePassword: '123456'
+});
+
+degiro.login()
+    .then(console.log)
+    .catch(console.error);
+