sqlite database. Allows us to build against system sqlite3 again, and get rid of the infamous symbol size mismatch warning reported several times on ports@. See https://bugzilla.mozilla.org/show_bug.cgi?id=445164 for why mozilla now hard-requires secure_delete, and https://bugzilla.mozilla.org/show_bug.cgi?id=546162 for the reasons they don't want to make that an option and forces us to do such hacks. ok jasper@