Fix example app cancel notification

The `lastId` should reflect the last id used not the next id to be used.
When the lastId is set to the next id to be used the `cancelNotif`
function will try to cancel a id not yet used.

Author: Henrique Shiraiwa

example/NotifService.js

@@ -40,6 +40,7 @@ export default class NotifService {
   }
 
   localNotif() {
+    this.lastId++;
     PushNotification.localNotification({
       /* Android Only Properties */
       id: ''+this.lastId, // (optional) Valid unique 32 bit integer specified as string. default: Autogenerated Unique ID
@@ -69,11 +70,10 @@ export default class NotifService {
       number: '10', // (optional) Valid 32 bit integer specified as string. default: none (Cannot be zero)
       actions: '["Yes", "No"]',  // (Android only) See the doc for notification actions to know more
     });
-
-    this.lastId++;
   }
 
   scheduleNotif() {
+    this.lastId++;
     PushNotification.localNotificationSchedule({
       date: new Date(Date.now() + (30 * 1000)), // in 30 secs
 
@@ -103,8 +103,6 @@ export default class NotifService {
       playSound: true, // (optional) default: true
       soundName: 'default', // (optional) Sound to play when the notification is shown. Value of 'default' plays the default sound. It can be set to a custom sound such as 'android.resource://com.xyz/raw/my_sound'. It will look for the 'my_sound' audio file in 'res/raw' directory and play it. default: 'default' (default sound is played)
     });
-
-    this.lastId++;
   }
 
   checkPermission(cbk) {