[Feature Request] Ability to set a due date #36

It would be helpful to set due dates in order to meet deadlines as well as help the assignee and their team meet internal and external SLAs.

Currently, we've been calculating deadlines using Zapier's internal Formatter: Date/Time event. Then we include that deadline variable at the top of issue descriptions to help the assignee notice them.

Please let me know if you have any questions.