Allow default answer reset to nothing#161

If I set a question to have a default answer, then decide later I don’t want it to default to anything, there’s no way for me to do so unless I delete and recreate the question, or remove and re-add all the answer choices if it’s a single select or multi select question. I’d rather not have to do this and mess up the logic of any other questions that might be attached to it. I think simply having a “None” selection in the default answer dropdown would be the easiest way to solve this.

+1!