Consider removing optional features

[nitely]

Optional features are a maintenance burden. For those wondering, they are usually the settings with a vale of False. The main issue is they are not well maintained, as they are usually contributions, requested features I don't use, or deprecated features. Does the comment file upload works? who knows, maybe it does, maybe it does not. They are not many, but if anything this issue shall serve as a remainder to keep it that way.

The features do have tests, so they probably work.