SSBC: Save last-selected filters for batch changes list page

Created by: courier-new

By default, the batch changes list has no filters applied when you first visit it, so all batch changes in any state will be shown. For certain user personas, batch changes in particular states may be of less interest. It is easy to filter them out by modifying the filters, but an additional enhancement would be to save the last-selected set of filters so that they are restored upon revisiting the list. This prevents a user who only cares about OPEN batch changes from having to repeatedly set the filter every subsequent time they view the list.