Handle environment variables on a heroku app from CLI

The heroku config commands of the Heroku CLI makes it easy to manage your app’s config vars.

cd myapp

# This will list all the env variables from your app
heroku config 

# Set env you want to add/update
heroku config:set S3_KEY=12345

# Get specific env
heroku config:get S3_KEY

# Removes specific env
heroku config:unset S3_KEY