*Authentication
=================================================================================================
    "TWITTER_OAUTH_CLIENT_SECRET": "@twitter-oauth-client-secret",
    "FACEBOOK_OAUTH_CLIENT_ID": "@facebook-oauth-client-id",
    "FACEBOOK_OAUTH_CLIENT_SECRET": "@facebook-oauth-client-secret",
    "GOOGLE_OAUTH_CLIENT_SECRET": "@google-oauth-client-secret",
    "GITHUB_OAUTH_CLIENT_SECRET":
    "GITHUB_OAUTH_CLIENT_ID":
    "TWITTER_OAUTH_CLIENT_SECRET_DEVELOPMENT": "@twitter-oauth-client-secret-development",
    "FACEBOOK_OAUTH_CLIENT_ID_DEVELOPMENT": "@facebook-oauth-client-id-development",
    "FACEBOOK_OAUTH_CLIENT_SECRET_DEVELOPMENT": "@facebook-oauth-client-secret-development",
    "GOOGLE_OAUTH_CLIENT_SECRET_DEVELOPMENT": "@google-oauth-client-secret-development",
    "GITHUB_OAUTH_CLIENT_SECRET_DEVELOPMENT": "@github-oauth-client-secret-development",
    "SLACK_SECRET": "@slack-secret",
    "SLACK_SECRET_DEVELOPMENT": "@slack-secret-development",

NOTE: API key has been hard coded in authentication.js file instead of using variable from now.js file
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*EMAIL
===================================================================================================
    "SENDGRID_API_KEY": "@sendgrid-api-key",
    "EMAIL_JWT_SIGNATURE": "@email-jwt-signature",
====================================================================================================

*Redis (DATABASE)
====================================================================================================
    "COMPOSE_REDIS_PASSWORD": "@compose-redis-password",
    "COMPOSE_REDIS_URL": "@compose-redis-url",
    "COMPOSE_REDIS_PORT": "@compose-redis-port",

    "REDIS_CACHE_PORT": "@redis-labs-port",
    "REDIS_CACHE_URL": "@redis-labs-url",
    "REDIS_CACHE_PASSWORD": "@redis-labs-password",

NOTE: 2 provider used for redis, thats why two different URL but We can use one provider.
=======================================================================================================

*RETHINK (DATABASE)
=====================================================================================================
    "COMPOSE_RETHINKDB_PASSWORD": "@github-compose-rethinkdb-password",
    "COMPOSE_RETHINKDB_URL": "@github-compose-rethinkdb-url",
    "COMPOSE_RETHINKDB_PORT": "@github-compose-rethinkdb-port",

NOTE: USED IN db.js file in PRODUCTION_CONFIG const. AWS based Rethinkdb variable do not need if we do not use AWS as Rethink DB host
======================================================================================================================================



========================================================================================================
*Unsed Variable
=======================================================================================================
OPTICS_API_KEY
APOLLO_ENGINE_API_KEY (commented out on code)

NOTE: do not find APOLLO_ENGINE_API_KEY in now.js
=======================================================================================================