Impact Custom User Groups: Conditions Based on Grades

[CaitlinByers]

We have multiple use cases for Custom User Groups in Impact with conditions based on a user's current grade. At this point, aside from uploading a CSV for a Custom User Group, we don't have a good solution for launching intervention messages for users based on their performance in a course. We would like to see a condition added to Custom User Group criteria that allows Impact messages to be targeted to users in specific grade ranges.