Flag to convert x-axis times into local dates
Related to issue #15 (closed) and #67 (closed) but not quite the same. It would be nice if there was a flag to have the x-axis show dates (e.g. 2019-04-10 12:53:42) instead of times (1.0 s, 6.7 d, etc.). This would match the default behaviour of dataviewer. The program could decide on an appropriate tick spacing but the user could force a particular one with another flag, e.g. --xtick-spacing 2d
for ticks every 2 days.
Furthermore these dates could be configurable with timezones, e.g. show UTC or local timezone or some other one.