lp1739286 default search box in Z39.50

lp1739286 default search box in Z39.50

This change tweaks the layout of search fields in the web client Z39.50
interface and adds radio buttons for the default search field to auto-focus.
The behavior is "sticky" without the need for an explicit Save action.  If the
current default field is not present due to a given combination of selected
services, then no field will be focused by default.

Signed-off-by: Jason Etheridge <jason@EquinoxInitiative.org>
Signed-off-by: Chris Sharp <csharp@georgialibraries.org>