This is the first step to make the exporter more testable.
Switch to Update using the Collecter Collect interface, due to not knowing all metricnames in all modules beforehand we can't use Describe and thus the full Collecter interface. Remove 'updates', it's meaning varies by module and doesn't add much.
This simple exporter exposes the systems unix time. It's useful to compare it to the prometheus server time and other targets to detect clock skew.