post
https://api.accelevents.com/rest/u/login/facebook/admin
User can use this api for login/signup into the system as a admin role.
We need to pass token here, which is generated after successful login into the Facebook account with the other details.
So if user account is already available than it will simply login into the system, if user is not registered in the system, than it will create new user into the system and automatically login into the system.