Optimize the activemembers admin
Closes no issue.
Short description
This MR makes the activemembers admin a lot faster by doing the following two things:
- Add
member
toraw_id_fields
in the inline for committee memberships. Before the entire list of members was copied for every committee membership. This resulted in html pages of several megabytes. - Remove duplicate queries (for different ids) by adding
select_related
calls in the right places.