Add HSTS Headers to Express Apps to Ensure All Requests are https Requests

In this lesson, we'll learn how to add HSTS headers to an express application so that all requests after the first request made to the application are https. We'll also learn about the HSTS preload list which will ensure that even the first request is secure. Even though we secured our session id cookie in the previous lesson, ensuring all requests go over https ensure that even if we add another cookie and forget to set it to Secure, we'll still not be transmitting it in cleartext over an http connection.