Nice panel in admin to show two-tier categories?

[osfameron]

e.g. , if Oxfordshire want to know which categories are sent to a district council, I believe I have to do:

• check list of IDs from http://mapit.mysociety.org/area/2237/covers.html?type=DIS,MTD,UTA,LGD,COI,CTY
• check categories in SQL with something like following

select 
    category,
    array_to_string(array_agg(body_name), ',')
from (
    select
        body.name body_name,
        category
    from contacts c
    join body on body.id=body_id
    where body_id in (2418,2417,2420,2421,2419)
    and c.confirmed
    and not c.deleted
    order by c.category, body.name
) s
group by category;