RFE: Add an indicator to the sorting when it can be sorted in asc or desc order

Description of problem:
Many lists have a sorting mechanism, but also sort in both asc and desc order. This is not obvious, as you have the choose the same option twice to get the inverted sort.

Version-Release number of selected component (if applicable):
3.7

How reproducible:
Easy always

Steps to Reproduce:
1. Go to the Glossary list
2. Click Sort, then Alphabetical

• list is sorted A-Z
  3. Click Sort, then Alphabetical

• list is sorted Z-A

The option looks the same. Perhaps an arrow showing direction on the currently selected sorting option would help.