Add new metric class

Added a separate metric class for code reorientation, might help clear
up some concerns with its performance
Add instrumentation/metric reports to Microcosm

We now support a somewhat coarse way of reporting time metrics through
the debug sink. Nothing advanced, as time spent in Microcosm is less
than 5% of the whole KokrotImg time, so we don't really need much
profiling down there.
Make KokrotViz aware of timing categories

In order to gracefully display the newly reported Microcosm metrics,
KokrotViz was informed of the categories that will be reported.