Bug 15100: MARC21 - make display of "Dates associated with a name" optional

 Bug 15100: MARC21 - make display of "Dates associated with a name" optional

With the changes for RDA now more subfields for the fields
100, 110, 111, and 700, 710, 711 are displayed.
One of them is $d - Dates associated with a name

This patch adds separate treatment of the $d subfield and
wraps it in a span with the class "authordates".
This makes it possible to hide the information with CSS.

To test:
- Make sure you have several records with $d catalogued
- Check the display in result list and detail page
  with and without the page.
- Check, if there is a difference in display
- Check if the dates are correctly wrapped in a span
- Try to hide the information, using the following
  entry in your *UserCSS preferences:
  .authordates { display: none; }

Signed-off-by: Hector Castro <hector.hecaxmmx@gmail.com>
Works as advertised

Signed-off-by: Jesse Weaver <jweaver@bywatersolutions.com>

Signed-off-by: Brendan A Gallagher <brendan@bywatersolutions.com>