Append reporter name to title in UI for law cases

[fbennett]

Law cases are reported in multiple reporters, and many legal styles require that references to several reporters be included in a consolidated cite to an individual case. citeproc-js handles the formatting issues correctly, but users will require a means of discriminating between items for the various reporters.

With this patch, a legal case item with a case name will include the reporter in parens following the title, in the UI. This allows the reporter to be identified in the selected items listing, so that the user can easily recognize and control the sequence of references.

(Discussions on the CSL list suggest that this "parallel citation" referencing style is conceptually different from the contemplated hierarchical items model. The special behavior of citeproc-js provides a lightweight mechanism for addressing the parallel citation use case. This tweak to the UI basically completes the feature.)

[dstillman]

(In [6226]) Closes #1687, Append reporter name to title in UI for law cases

Slightly modified verison of Frank's patch