Goal: 
As a user, I am able to set an open-ended start/end date filter.

Where:
• Instance date filter 
• Flow Node date 

To do:

• Add options for Between..., Before..., and After...
• Display a single date input field for the new sections 
• Display appropriate filter preview  

Additional fix: 
• Close popover when clicking outside of it 
If no edit has been made, current state persists. 
If no selection exists - can close pop over, but filter cannot be added.