Feature/dig idn2 recent

Hello,

As a part of transition from IDN 2003 to IDN 2008 on Fedora, we have prepared libidn2 patch. It is already tracked under RT #46788. Fedora Bug

This is squashed down version. It contains new dig option +idnin, which allows to process invalid domain names much like dig without IDN support. Only libidn2 version 2.0 and higher supports translation back into locale, which enables by default +idnout. Unlike original libidn patch it will pass dighost system test when enabled. Because we no longer need libidn support that was never accepted, last patch also removes support for original libidn. Transitional mode of libidn2 should be sufficient as a replacement.

Closes #26 (closed)