503 highlight (un)hold button based on call state
Closes #503
When there are no call -> Somewhat disabled When there is an active call -> Enable button When there is a call on hold -> Highlight
Do not update/delete: Banner broadcast message test data
Do not update/delete: Notification broadcast message test data
Closes #503
When there are no call -> Somewhat disabled When there is an active call -> Enable button When there is a call on hold -> Highlight