Reset button, to reset the weight all back to 0 or to alpha order

Problem/Motivation

@SocialNicheGuru asked for this feature in #2224881: Can I specify an initial/default sort order? → .

In a view you have Draggableviews:weight as the primary sort, then other sorts, such as Content:Title, as secondary. Before the view is ordered, it will be sort by Content:Title, as all weights are 0 (if using native handler). After the weight have been saved, he wanted the option to reset it back to Content:Title.

Proposed resolution

Add reset button option in the Draggableviews:weight sort option. This will either reset all the weights to 0 or remove them from the database (native).