Create a "Clear Draft" button for question creation

[lsabor]

A bug happens when trying to duplicate questions (definitely as a continuous group but probably other types) where if you have a draft already, it conflicts with the attempted duplication.
In an ideal world, the duplication wouldn't conflict with the draft at all (maybe a url flag would suffice), but I think a cheaper and faster but almost as good alternative would be to have a "clear draft" button on the page to reset the cached draft to null. Doing that would fix the original issue.

[SylvainChevalier]

@lsabor but you'd need to clear the draft before duplicating, no? Could we instead clear your drafts when you click the duplicate button directly?