add active status for cases when one is not closed but not active either

abby said:
 I'd love to have a status field as a manually input field. We have program, owner, and mute/don't mute... but I think there's also a need to have some folks not muted but noted as "closed". I could also add this as text to the mute column - ie, have three possible values: TRUE, CLOSED, ACTIVE.