Allow multiple selection in status and category sortings

Description: Allow multiple simultaneous selections when sorting by category or status in the website feedback board (or changelog as well) Problem: Currently only one category or status can be selected to display the search results for that category or status. Then I have to do a separate search if I want to see results for another category or status. Benefit: User can view all posts under more than one category (or status) at the same time on the same search and not on separate searches for each category/status. Maybe make each category a selectable checkbox and then be able to select various categories/statuses simultaneously