- add optional libmdnsembedded support to configure
- add HAS_MDNS and HAS_MDNS_EMBEDDED for supporting zeroconf through mDnsResponder
- cleanup ifdefs use HAS_MDNS and HAS_MDNS_EMBEDDED (similar to what we do with HAS_AVAHI already) instead of making TARGET_blah assumptions - rename Zeroconf*WIN.* to Zeroconf*MDNS.* and move it into its own subdir mdns - its not windows specific anymore - add support for libmDnsEmbedded for allowing zeroconf support without running daemon (embedded server)
- add mdnsresponder to depends and build it for android