2006. [security] Allow-query-cache and allow-recursion now default

2006.   [security]      Allow-query-cache and allow-recursion now default
                        to the builtin acls "localnets" and "localhost".

                        This is being done to make caching servers less
                        attractive as reflective amplifying targets for
                        spoofed traffic.  This still leave authoritative
                        servers exposed.

                        The best fix is for full BCP 38 deployment to
                        remove spoofed traffic.