Update readme

Author: Shashank Raj

README.md

@@ -155,12 +155,12 @@ Beaconstac.getInstance().overrideBeaconstacNotification(new BeaconstacNotificati
 __7. Add additional values to your webhooks__
 
 ```java
-beaconstac.addValuesToWebhook(MY_KEY, VALUE);
+Beaconstac.getInstance().addValuesToWebhook(MY_KEY, VALUE);
 ```
 
 OR
 ```java
-beaconstac.addValuesToWebhook(MY_KEY_VALUE_HASHMAP);
+Beaconstac.getInstance().addValuesToWebhook(MY_KEY_VALUE_HASHMAP);
 ```
 
 __8. Set user's name__

examples/BeaconstacExample/app/src/main/java/com/mobstac/beaconstacdemo/MainActivity.java

@@ -81,7 +81,7 @@ public void onRuleTriggered(MRule rule) {
     private void initializeBeaconstac() {
         if (checkPermission()) {
             try {
-                beaconstac = Beaconstac.initialize(getApplicationContext(), "08ddda7aabcbecfa54b29f6d032d7d289eb241b5", new MSErrorListener() {
+                beaconstac = Beaconstac.initialize(getApplicationContext(), "MY_DEVELOPER_TOKEN", new MSErrorListener() {
                     @Override
                     public void onError(MSException e) {
                         Log.e("Beaconstac", "Initialization failed");