#14 UI: huge lists are confusing

[zaarkov]

group them together, or use dropdowns

e.g.:
"create domains": group users by domain. first select domain, then user in domain
"create/revoke domainadmins": this matrix doesn't work at all. first select domain, if not already clear that one is selected (url shows /vmsa/domainadmin/createdomainadmins/domain/example.com/), then user (like above) to elevate/remove