Drill down for queries with "compareDateRange"

Hi !

We've been developping an embedded analytics module based on cube, with an extensive use of drill down.
While it's working fine for most queries, it's not yet supported for queries with a date range comparison (and we plan to use it quite a lot)

For instance, the graph below is made from a comparison with a compare date range.

Would it be possible to extend the coverage of drill down ?

Many thanks in advance for your support on this

No files, tests, or entry points are named. Start by locating the drill-down handling and the query path for compareDateRange, then determine how comparison queries should expose drill-down results. Done means drill-down works for queries using a compare date range.

Written by the indexing model from the issue text.