Downvote button: add confirm + slider

[KrNel]

The downvote option has serious issues. I went to click upvote, and hit downvote on my android by accident. A 100% flag was sent, costing 2.5% voting power.

This is really annoying that there hasn't been at least a confirm dialog added since the inception of the downvote. Please add it.

Also, a 100% downvote/flag is limiting as well. Hardly anyone wants to use that much power on a flag. Please add a slider as well.

But at the very least, add a confirm dialog box.

Thank you!