Summary:
Makes filter counts take other column filters into account.
- Changes the summaries rows to reflect hidden rows:
- hidden rows are added to the `Other Values` summary
- show the unique number of other values as `Other Values (12)`
- Also, adds a sort button to the column filter menu
Test Plan: Adds browser test.
Reviewers: paulfitz, jarek
Reviewed By: jarek
Differential Revision: https://phab.getgrist.com/D2861
