+ Parse and convert multibyte hostnames according to IDNA (with IDNA support).
+* PARSE_TOIDN_2003
+ Explicitly request IDNA2003 implementation if available (libidn, idnkit or ICU).
+* PARSE_TOIDN_2008
+ Explicitly request IDNA2008 implementation if available (libidn2, idnkit2 or ICU).