Release v2.3.0

NodeJS 14.5.0 is required

• (klein0r) Added hourly, weekly, monthly, ... averages
• (klein0r) Added promises to avoid parallel execution of tasks (lead to incorrect calculations)
• (klein0r) Fixed init values for save/temp
• (klein0r) Added option to enable statistics for objects via sendTo
• (klein0r) Allow sum delta to substract values (negative delta)
• (klein0r) Delete states when option in unchecked
• (klein0r) Removed dayMin and dayMax from avg (use minmax for that case!)
• (klein0r) Fix: Calculation of avg when no change of value