v5.30.3

Require getaddrinfo which has been available since 2003.

Provide server host for SSL by using gnutls_server_name_set(3).
Thx to Guillaume Jactat.

Obey [host]:port notation for IPV6
https://tools.ietf.org/html/rfc3986#section-3.2.2

Minor fixes to 'make dist' handling. Thx to Hugh McMaster.