Configuration to enable working day calculation instead of working time calculation

[arolfes]

To enable WorkingDayCalculator instead of WorkingTimeCalculator:

taskana.workingTime.useWorkingTimeCalculation=false
taskana.workingTime.timezone=<YOUR TIMEZONE>

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Release Notes:

Restore the old behaviour to calculate the planed and due date based on day and not based on milliseconds

To enable WorkingDayCalculatorImpl instead of WorkingTimeCalculatorImpl:

taskana.workingTime.useWorkingTimeCalculation=false # default value is true
taskana.workingTime.timezone=<YOUR TIMEZONE>

Bugfix in ServiceLevelHandler to recalculate the due date when the classification key has changed.

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