Possible compatibility problems with earlier versions marked with '*'.
+For ZOOM connection, the options targetImplementation{Id,Name,Version}
+are set when Init Response is received.
+
+New function ZOOM_connection_error_x similar to ZOOM_connection_error
+but returns diagnostic set as well.
+
New function yaz_strerror which is a portable wrapper for
strerror/strerror_r/GetLastMessage.