Document Sorting Logic

[sosiology]

To increase transparency, document the logic around the sorting. This is consolidated in the sortingvalues.ts

[adintegra]

Note: This description is draft, i.e. work in progress

With reference the original issue (#2032), the current sorting for hierarchies is indeed as follows:

• Hierarchies are sorted one level at a time, starting at the root, before branches are sorted
• Only the hierarchy headings are sorted, leaf nodes (i.e. values at the lowest level are not)
• For the dataset in question, the hierarchy within the cube is as follows:

[ptbrowne]

FYI there is also this document that could be improved with the results from this ticket.