Log Message:
Version 2.0.3 (released 2017-07-24) [beta]

** %IDN2_USE_STD3_ASCII_RULES disabled by default.
 Previously we were eliminating non-STD3 characters from domain strings
 such as _443._tcp.example.com, or IPs 1.2.3.4/24 provided to libidn2
 functions. That was an unexpected regression for applications switching
 from libidn and thus it is no longer applied by default.
 Use %IDN2_USE_STD3_ASCII_RULES to enable that behavior again.

** Fix several documentation issues

** Fix build issues

** Modernize gtk-doc build infrastructure.