Mention OPT TT inclusing in Changelog
[API 0.510] "scope_id" attribute for upstreams
[API 0.511] stubs may do dnssec

And return of GETDNS_RETURN_DNSSEC_WITH_STUB_DISALLOWED has become optional
[API 0.512] caller destroys dict_get_names list
[API 0.513] Update spec date and editor