#1404 Enhance 'Empty Containers' cleanup reports

[Ahasuerus]

The two 'Empty Containers' cleanup reports -- one for magazines and the other one for anthologies and collections -- let moderators "ignore" records. When the reviewing moderator clicks "ignore", he or she is redirected to the main cleanup page as opposed to the sub-page that s/he is on.

We want to change the behavior of the "Ignore" link to redirect the moderator back to the currently displayed page. If the re-displayed Web page has no records left, it should inform the moderator about it and display a link back to the main report page.

[Ahasuerus]

Implemented in:

edit/empty_containers.py
mod/TARGETS
mod/resolve_empty_containers.py

Installed in SVN 609 on 2021-03-26. Closing the FR.