Add `requested` resources to cluster monitoring
We should track how much CPU and Memory is being requested, as if this runs out pods will become unschedulable. We can simply add another series to the existing two charts to display this.
Note that this will require some additional work, as we currently do not have a method to display the results of two different queries on the same chart. The good news is the scale is the same, so we don't need two different Y axis.