Charts:
 - rolling average and deviation of rankings
 - average ranking at the beginning of each championship season
Calculation:
 - modifying disparity by time of year (or by ranking deviation from last 3-4 months)

TODO:
 - detect grid penalties (ergast.races.grid != eragst.qualifying.position || non-ergast.qualifying.position != ergast.races.grid)
 - detect multi-heat races on chicanef1