Add editorial ordering

[psnewslab]

cf. classic, basically move published_date one up the tree.

var SORTS = {
var SORTS = {
  'editorial' : {order: {order: 'desc', missing:'_last', unmapped_type: 'long'}},
  'newest_first' : {published_date: {order: 'desc', missing:'_last', unmapped_type: 'long'}},
  'oldest_first' : {published_date: {order: 'asc', missing:'_last', unmapped_type: 'long'}}
};