C-ares is required, so don't mark it as optional. Add Win64 download
URLs and list them first. Zlib is part of our vcpkg bundle.
Change-Id: I232f4df988aa12afde0b66fff203187136504e94
Reviewed-on: https://code.wireshark.org/review/35700
Reviewed-by: Gerald Combs <gerald@wireshark.org>
Petri-Dish: Gerald Combs <gerald@wireshark.org>
Tested-by: Petri Dish Buildbot
Reviewed-by: Anders Broman <a.broman58@gmail.com>