Issue Summary

Stories: Time Stamps in Export are confusing

Steps to Reproduce

1. Login. 
2. Go to Kanban Board with multiple columns mapped to States. 
3. Add Story. 
4. Move Story between columns multiple times. 
5. Go to Stories Grid. 
6. Filter grid to Story you were moving on Kanban Board. 
7. Export. 
8. Open the downloaded file. 
9. Check State change columns and timestamps in them

Expected Results

1. When Story is moved to some State all Future States time stamps should be removed;
2. When Story is moved from column to column that is mapped to the same state we shouldn't update time tamp for this state. We are already tracking this action in the Audit log, so no need to update timestamp.

Actual Results

1. In some Cases Story that is in let's say Pending Approval State might have In Progress Date filled in Export. I think that we need some mechanism that will exclude such possibilities.
2. When Story is on a Kanban Board with Multiple Columns mapped to the same state moving Story between these columns updates State Time Stamp.

Workaround

Currently there is no known workaround for this behavior. A workaround will be added here when available