LP#1290496: The quest for knowledge is over

LP#1290496: The quest for knowledge is over

An apparently bad query plan causes Z39.50 searches of local
catalog to take an extremely long time to complete.  One theory
is that metabib.rec_descriptor is the culprit, but that has not
been verified.

This commit works around the immediate problem, but will need to
be revisited.  Some questions include:

1) Should we rewrite parts of open-ils.search.biblio.multiclass
(and the underlying storage methods) to use the new attr structures
more directly, rather than through a view of a view?

2) Alternately, should we rip it out?  If so, we will need to also
remove/nullify the "use_staged_search" option, since there will be
no functional non-staged offering.

Signed-off-by: Dan Wells <dbw2@calvin.edu>