New Extension 15

1. PrescriptionServiceBean.getAvTotalPriceBetweenDates() --> Overrides
and contains logic of the calculation
2. JMS PrescriptionStatisticsListener.averageTotalpricePerPrescription
3. PharmacyHO04-EJB: PrescriptionStatisticsDO
result.setDoubleAverageNumberOfItemsPerPrescription
4.  PharmacyHO04-EJB PrescriptionStatisticsDO: getters and setters
5. PharmacyHO04-EJB PrescriptionStatisticsPage: set getter for Java:
getAverageTotalpricePerPrescription()
6. PrescriptionStatisticsPage.page.xhtml:
value="#{prescriptionStatisticsPage.averageTotalpricePerPrescription}"

ToDo: Repeat for c#