#929 Standardize record deletion rules

[Ahasuerus]

At this time the rules for record deletion are as follows:

1. Publications can only be deleted manually. There is a cleanup report that finds publications without titles.
2. Titles, including titles with no publications, can only be deleted manually. There is a cleanup report that finds titles (except ESSAYs, POEMs and SHORTFICTION) with no publications.
3. Series, including empty series, can only be deleted manually. There is a cleanup report that finds empty series. We have an FR to "Enable series auto-deletion".
4. Authors are deleted automatically when the last title associated with the author has been deleted.
5. Publishers are deleted automatically when the last publication associated with the publisher has been deleted.
6. Publication series are deleted automatically when the last publication associated with the publication series has been deleted.
7. Awards, award categories and award types can only be deleted manually. Empty award types and award categories are flagged by cleanup reports.

It would be desirable to standardize the rules for automatic record deletion. The following record types would be affected: authors, series, publishers, publication series. The updated algorithm would check if the about-to-be-deleted record has additional information associated with it: notes, Web pages, biographical data (for authors.) If it does not, then the record would be deleted. If it does, then the record would not be deleted; instead it would appear on a record type-specific cleanup report. The new cleanup reports would be periodically reviewed and any relevant data would be migrated to existing records prior to manual deletion.

The proposed algorithm would require three new options:

1. Delete Author
2. Delete Publisher
3. Delete Publication Series

It would also require the creation of three cleanup reports for authors, publishers and publication series.