Support 'True-Client-IP' header for AWS setup

[OlesYudin]

Is your feature request related to a problem? Please describe.
When you setup CloudFront as reverse proxy to redirect customdomain.com to canarytokens.org in the history of alert you will not see real client IP, instead you will see CloudFront Edge Location IP. This is because CloudFront does not support X-Real-Ip header.
Using this guide you can create CloudFront function that will pass real user IP into 'True-Client-IP' header. My question is it possible to add 'True-Client-IP' header that will be used as user IP.