Analytics
Add the filter for Backend API in the existing analytics views/graphs
If we have to add new views/graphs then it is fine (probably).
If we replace the old ones then it might break for current customers

DEV NOTES:
First, we need Product to describe what is expected, interaction, provider and dev portal use.
Second, wire framing about how it should look like and what kind of ux needs to provide.
Third we need to analyze how open to change is the Stats library to include a separation of metrics (backend - product)

The list of metrics we currently show in the filter of each graph only includes product metrics. A quick win to start with can be extending that list from metrics to all_metrics. We need to make sure the system_name of backend API metrics is correct, since porta may strip out the backend ID suffix. Next step would probably be how to differentiate product metrics from backend API metrics in the UI (label, icon?)