C-Ares and IPv6 is no longer a bad combo.

tests on machines that have broken DNS configurations (such as
those configured to use OpenDNS).

changed ssh.c to use HAVE_LIBSSH2_SESSION_BLOCK_DIRECTION define provided by libssh2.h; removed related define block from ssh.h.

  https://bugzilla.redhat.com/show_bug.cgi?id=427966 which was libcurl closing
  a bad file descriptor when closing down the FTP data connection.  Caolan
  McNamara seems to be the original author of it.

c-ares can work even with no advapi32.dll at all.

Made OS400 version compilable again

RtlGenRandom, has been located or not. This function is only available on
WinXP and later. When unavailable c-ares uses portable rand() function.

  CARES_HAVE_ARES_LIBRARY_INIT and CARES_HAVE_ARES_LIBRARY_CLEANUP
  to ease the use of new capabilities.

- Move ares_version() prototype to ares.h

Introduction of ares_library_init() and ares_library_cleanup()

  no_proxy which made it not skip the proxy if the URL entered contained a
  user name. I added test case 1101 to verify.

Extend displaying of logfiles upon first server start-up failure for http, https, ftp, ftps and tftp test harness servers.