* dbus/dbus-address.c: (dbus_address_entry_free):
	Free key and value lists.

	* dbus/dbus-internals.c: (_dbus_type_to_string):
	Add the types we didn't have.

	* dbus/dbus-marshal.c: (_dbus_marshal_get_arg_end_pos),
	(_dbus_marshal_validate_arg):
	Add NIL types.

	* dbus/dbus-message.c: (dbus_message_set_sender):
	Remove todo about being able to set sender to NULL.

	(dbus_message_set_is_error_reply),
	(dbus_message_get_is_error_reply):
	* dbus/dbus-message.h:
	New functions.

	* dbus/dbus-protocol.h:
	Add error reply flag.

	* test/data/valid-messages/opposite-endian.message:
	Add NIL type to test.