Code style changes, add benefit & promoters screen

* PHP variables to camelCase;
* Finished “add benefit” screen;
* Smaller index.php file;
* Lazy images now load when detail click is triggered;
* New promoters screen;
* New promoters functions: getBenefitUsersByPromoter(),
getPromoterStats() and improved getPromotersStats();
* EventTable code style corrected;
* Now promoters only can add someone to a VIP List if it has status = 3;
* New crush panel layout;
* More discreet alerts;
* Some navbar changes.