todo:
+* finish DBUS stuff:
+ - allow NUL bytes in TXT records
+* add internal error codes
* release!
+later:
+* support for special domain PTR records based on local IP subnet address
+* Changes resulting in updated RFC of 7th June 2005:
+ * Defer responses to replies with TC bit set by 400-500msec
+ * Defer unicast responses the same way as multicast responses
+
done:
* Probing/Conflict resolution
* uniqueness
* enlarge packet in case a record/query is too large to fit in a normal packet
* reflector
* test against apple test suite
+* sensible logging
+* c++ support
+* drop trailing dot on avahi_normalize_name()
+* add entry_group::reset()