By Logan Mahan On Thursday, Twitter announced it would be expanding its experimental downvote feature to a global audience. Testing of the new feature began last year and was accessible to a select group of internet users. After receiving positive feedback on its decidedly negative new trick, Twitter is now extending the button to iOS and Android users worldwide. The button may remind you of a similar feature that’s been a part of Reddit since 2005. Upvotes and downvotes on the popular forum website are used to highlight relevant and favored replies and posts from users in a particular subredd…