Force colors to match based on series label

[wrouesnel]

When putting a chart together, sometimes I have the same series label on several pieces of data (i.e. load, cpu, network etc.) and have got those plotted so all are visible (i.e. cpu and network at the top and bottom of the same graph).

In this case, I would like the auto-coloring to actually force series with the same label (i.e. the instance name) to have the same color so one can tell at a glance what the CPU/Network for a one instance on the same graph is doing compared to others.