BKND-42 Allows the service to receive an array of events

Checks the request if there is a value for the key "event_list", if not it does as it used to. If there is a value it will parse it as JSON and attempt to grab `screen_name`, `event_name`, `hotel_id` and `timestamp`. `timestamp` /can/ be good to have since the events are inserted pretty much at the same time.

Now it will take either a request like this
```
{
 device_code
 tmp_secret_key
 app_secret_key
 screen_name
 event_name
 hotel_id
}
```
or this
```
{
 device_code
 tmp_secret_key
 app_secret_key
 event_list [
             {
              screen_name
              event_name
              hotel_id
              timestamp
             }
            ]
}
```

The code will just create an entry for each event since the database structure is unchanged.