tests/integration: iterator testcases from Unbound (+BSD license)

tests/testdata/LICENSE

tests/testdata/iter_class_any.rpl

tests/testdata/iter_cname_cache.rpl

tests/testdata/iter_cname_double.rpl

tests/testdata/iter_cname_nx.rpl

tests/testdata/iter_cname_qnamecopy.rpl

tests/testdata/iter_cycle.rpl

tests/testdata/iter_cycle_noh.rpl

tests/testdata/iter_dnsseclame_bug.rpl

tests/testdata/iter_dnsseclame_ds.rpl

tests/testdata/iter_dnsseclame_ds_ok.rpl

tests/testdata/iter_dnsseclame_ta.rpl

tests/testdata/iter_dnsseclame_ta_ok.rpl

tests/testdata/iter_domain_sale.rpl

tests/testdata/iter_domain_sale_nschange.rpl

tests/testdata/iter_donotq127.rpl

tests/testdata/iter_dp_turnsuseless.rpl

tests/testdata/iter_ds_locate_ns.rpl

tests/testdata/iter_ds_locate_ns_cname.rpl

tests/testdata/iter_ds_locate_ns_detach.rpl