Add "Expand All" and "Collapse All" Buttons to Workload Balancer

[#1]

The Resource Scheduler as functionality where the user can "Expand All" and "Collapse All" to show and hide, respectively, all projects to which a resource is assigned a task. This functionality needs to be present in the Workload Balancer as well.

[#2]

I fully agree and upvote this comment, as it would make the Workload Balancer function so much more user-friendly. It is a hassle to 'expand' one by one each time the view is refreshed.