Allow search optimization settings to be configurable from admin forms. Also allow default profile to be set

1. for large db's we definitely dont want the "order by" (tmp table creation) in the search query
2. we also should allow folks to turn of alphabetical pager and hence reduce load on system

Finally we should alllow exposing a default profile rather than exposing name/phone/email/address (4 left joins there) for large db's. This can also improve performance significantly