Adds prove it buttons to the figure template

Fixes #3376 

@aaronschachter 
Let's set a `button_text` variable that displays what copy to display in the button.  this should be

````
function paraneue_dosomething_preprocess_user_profile(&$vars) {
  if ($doing = $vars['doing']) {
    foreach ($doing as $delta => $value) {
      $image = dosomething_image_get_themed_image($value['nid_image'], 'landscape', '300x300');
      $item = array(
        'url' => $value['path_alias'],
        'title' => $value['link'],
        'image' => $image,
        'description' => $value['call_to_action'],
      );
````