directly pushing.

directly pushing.

- renamed private methods to addXXX for consistency
- made them non const member functions (for the same reason why
  addNXDOMAINProof can't be so)
- renamed variable 'zone' to 'finder' to adapt to class name change

very rare and shouldn't happen with a valid zone)

cannot be const because they modify response_.
maybe we should pass the response via method parameter rather than at
the construction time, or even make this a simple free function, rather
than a class.  but that will be a separate discussion.

of the NXDOMAIN NSEC.

this is necessary for NSEC query handling.

This fixes problem with
	socket.error: AF_UNIX path too long
on many builders.
(That is ticket #360.)

of different types covered.  Not directly related to the main subject
of the branch, but this enhancement will make writing tests easier.
confirmed this change doesn't cause regression for other tests.

this change is incomplete: we still need a wildcard proof.

1213 failed to take into account a change in zone configuration
options, causing the IXFR-in test to fail.

Those tests will be reenabled once #1313 is implemented.

The usual problem with EXPECT_EQ(NULL, ...), it doesn't like the type.

that didn't expect NSEC.

but apparently forgot to type in '&')