Switch the default backend to BDB.

configure

configure.in

tests/Makefile.in

tests/scripts/all

tests/scripts/defines.sh

tests/scripts/start-master

tests/scripts/start-master-nolog

tests/scripts/test000-rootdse

tests/scripts/test001-slapadd

tests/scripts/test002-populate

tests/scripts/test003-search

tests/scripts/test004-modify

tests/scripts/test005-modrdn

tests/scripts/test006-acls

tests/scripts/test007-replication

tests/scripts/test008-concurrency

tests/scripts/test009-referral

tests/scripts/test010-passwd

tests/scripts/test011-subtree-repl

tests/scripts/test012-glue