Traveloka.com API SDK

With great help from BEI Team, especially @fajrin and @christianto.handojo, now we have a clean and concise way to create public API services for Traveloka.com. You might be already aware about how to decouple from frontend-fx module, and we think you also need to know about the Traveloka.com API SDK page. Some benefits of using the new SDK are simplified dependencies and reduced build time (from 11 to 2 minutes in our case) since you no longer need to depend to application-* modules just to get the API classes. Long story short: