Add support for sending logs to a text file

[meareal]

In development mode, we get logs in the console. Ideally we would be able to log every request and response to a text file we specify in dab-config.json file.

In the past, I have added a middleware component to our custom Web APIs to log every request and every response in the InvokeAsync method.

[seantleonard]

Thank you for your suggestion, @meareal. We are now tracking this ask in #1818