Allow others to see DND status through the phone settings not just the app

This should match the physical phone settings as well. If I put my phone on DND, it does not show on the phone screen (which the preset buttons should turn red, as it does when someone is on a call) nor on the app to others that I'm busy. I shouldn't have to put my phone on DND through the app in order for others to see this. RingCentral really has taken a step back compared to Mitel.