Add an Approval Due Date

Description - Approvals should have a due date field

Why is this feature important to you - Many of the processes that require approvals in my line of work are timely and need to be received before certain activity can take place.

How would you like the feature to work - I would like a due date field added to the approvals object to drive timely notifications when action is required and when. 

Example: 
A campaign (Project) has a list of drops (Tasks), with fixed start and end dates. A drop cannot occur until final approval has been received.  I would want to set a Task Approval due date somewhere between 3-7 days prior to the set start date and have that trigger notifications to the Approver that they've been asked to approve and when we would need it, sending reminders as the due date approaches.