Add a way to limit the number of associated courses that display in the catalog

[Jane Sandberg]

When a title is associated with a course (and the course materials module is enabled), the following interfaces display information about the course:
* OPAC search results page
* Staff catalog search results page
* OPAC record display page
* Staff catalog bib summary panel

There should be a maximum number of courses that display in these screens. Ideally, system administrators would be able to set different limits for different screens (the OPAC record display page can probably accommodate more course links than the search results pages can).

Possibly, there could be a "...and 12 more" type link that displays the remaining courses.

The motivation here: foundational texts might be associated with a large number of courses, especially in a larger consortium. Displaying a huge number of courses in these screens would be overwhelming and ultimately unhelpful for users.