todo:
* Probing/Conflict resolution
* uniqueness
+
* defend our entries on incoming goodbye
* Unicast responses/queries
* Legacy unicast
-* Known-Answer suppression server part
-* Truncation
+* remove expression "rrset" from source files
+
+* add SRV and TXT records referenced from PTR records automatically to packet
+* add A and AAAA records referenced from SRV records automatically to packet
+
+* name compression
+
+* respect escaping in name serialization
done:
* really send goodbye packets
* refresh subscribed records only
* FLX_DNS_TYPE_ANY support
* Known-Answer suppression client part
+* Known-Answer suppression server part
+* make flx_server_add_text() and flx_server_add_service() variadic functions