Draftpaper 0.7.3

A year of readings on the graph.

• A year of readings on the graph, on a logarithmic time scale: now at the right, then the last 5 minutes,
  the hour, the day, the week, the month and the year, each period ticked and named. draftpaper metrics keep (draftpaper-metrics.service, part of the session) samples every 5 s into six periods of fixed slots
  (5 s, a minute, a quarter hour, an hour, a quarter day, a day): each slot keeps its count, sum, least
  and most, so the year is some 870 slots a reading. One line through all the periods, the bold reading's
  least to most a band under it, broken where nothing was kept. The file is in the runtime directory,
  kept on disk every 5 minutes; draftpaper metrics prints it. The shell no longer samples on its own.