Feature Request - Show time trends

[afg1]

One of the resons we are using tower is the ease of monitoring our workflows - its great, thanks!

However, one aspect is missing. It would be fantastic to be able to look at time trends for a few metrics.

What I'm thinking of is for example visualising the CPU hour usage of a given workflow over time as we try to optimise it.

This could be extended to filter by labels and monitor usage over time of a class of workflows, and/or extended the other way to look at more metrics over time