Update to be on par with latest mdns.h state

[talaviram]

I've updated mDNS-cpp to be in-sync with changes in mdns c including bug fixes.

I've made it in gradual commits to ensure I'm following actual changes so it might be useful to squash those.

I've compiled and tested it on macOS so I'm sure the Unix side would work for most flavors. ~~Sadly, I've yet to test the Windows side.~~

I've also pushed relevant changes so now everything was tested on macOS and Windows.

[boulabiar]

Is there any need for "Ignore link-local addresses"?

In my use case I search for devices exposed using a default link-local address.

[talaviram]

I have no clue :) I’d suggest opening an issue or wondering about this on the mdns.h / C side as it was merged there.