Warehouse exams views cleanups and simplifications

[Ghislain Hachey]

Over the years views have been created and polished with better naming convention following a more consistent approach. But no cleanup is done and this accumulates cruft making maintenance and user training more difficult. This issue will be a round of cleanup with Exams related views.

[Ghislain Hachey]

Care must be taken to adjust the backend if the older views are used. They are more often used in JasperReports and thus changes are needed in the https://github.com/PacificEMIS/pacific-emis-reports/ repository also.