Budget dashboard support for per pupil expenditure by education levels

While we have support to produce this, it is not as straight forward as it should be. One either needs to get the enrollment data from Schools dashboard, then total expenditure from Budget dashboards to computer the indicator. Or, load the data from the warehouse in a workbook and produce it there. Considering this is a very basic indicator we need to add it t budget dashboard.

Note that a similar work relates to this in #1330