data: Ignore info events for detail and time stats

We have had an issue for some time with Gitaly logs where info events, those that do not include a status code or duration but may contain information regarding system utilization, were included in the total number of events. Info events accompany standard log entries for the same request, so counting these would essentially double the RPS for some RPCs, particularly upload-pack requests.

RawDataMap already ignored these, but the --verbose output and --interval would not. Update DetailTimeMap, RawTimeDataMap, and UnsortedTimeMap to disregard these entries, which are only consumed by top and plot.

Closes #33 (closed)