Add checks/alerts for "unrealistic" forecasts

[braddf]

From Full-Stack Chat notes:

• Idea: checks for normality, e.g. shape of data,
• Idea: Massive changed from one forecast period to the next (I.e. jagged shape / unrealistically steep ramps)
  E.g. >+100% increase, or >70% decrease
  -Idea: Meaningful discrepancies between models, i.e. Day-Ahead should remain true-ish to the Intra-Day, maybe within 20%
• Can test these alert boundaries on the Backtest
  • Aim to get of the order of 5-10 false-positives each year