Use case or problem
When creating a colour scheme for graph view there are instances where one file matches multiple groups. In these cases the first group is applied as a colouring rule. However if you wish to have another group prioritized there are no easy way to change the prioritization.
By implementing functionality to reorder the rules it would be easy to change the priority of the rules, simply by moving them up or down in the list.
Current workaround (optional)
As it is now you have to delete the groups and then recreate them in the order you wish to use.