Wishlist: additional sorting for Call Number browse

[Benjamin Kalish]

Call Number Browse displays materials in (to the best of its ability) call number order, but when multiple items share the same call number their order is more or less arbitrary from the user's perspective.

The default sort for items that share a call number should be something sensible (probably alphabetical by author) and the user should be able to change the sort to any of the following:
- Alphabetical by author
- Alphabetical by title
- Pub date (descending)
- And possibly acquisition date (descending)

The first two are useful because they mimic the way libraries often arrange such materials on the shelf and the last two are useful to patrons that want to explore the collection and are interested in the newest materials or additions.