Add contextual links during template_preprocess_views_view

Problem/Motivation

Draggableviews adds 'Order view' contextual link using `hook_contextual_links_view_alter()`. In this function it needs to build the view to check if it has an order path, then adds it. It builds every view, including non-draggableviews views, because it does not have the information to tell if its a draggableviews or not.

Proposed resolution

Views adds it contextual links using template_preprocess_views_view(&vars). We should use this hook and create them inside this function, as the view is already built in it.