TPac: Avoid long-running, unintended empty searches

TPac: Avoid long-running, unintended empty searches

If a page that executes a search is accessed with no viable search
query, cut the search short to avoid meaningless, long-running searches.
This primarily affects direct links to record detail pages.  For
example:

http://example.org/eg/opac/record/123

The RD page attempts to load the currrently active search (for paging) and,
if there is no query, will search for strings like 'site(BR1) depth(2)',
which are unintended and quite slow, which delays page rendering.

---

While we're in there, let's silence the following Apache error log
warning by ensuring that int() gets a value.

Use of uninitialized value in int at
/usr/local/share/perl/5.10.1/OpenILS/WWW/EGCatLoader/Search.pm line 192.

Signed-off-by: Bill Erickson <berick@esilibrary.com>