TPAC: Add a progress spinner after pressing search on Advanced Search

TPAC: Add a progress spinner after pressing search on Advanced Search

Advanced Search had no indication of progress once you've submitted
a search. We should add a "progressbar_green.gif" like the basic search
has, so the user knows their search is in progress, and (hopefully)
avoids them from hammering submit to get a result.

Signed-off-by: Michael Peters <mrpeters@library.in.gov>
Signed-off-by: Lebbeous Fogle-Weekley <lebbeous@esilibrary.com>