c-ares version 1.16.1

Security:
 o Prevent possible use-after-free and double-free in ares_getaddrinfo() if
   ares_destroy() is called prior to ares_getaddrinfo() completing.  Reported
   by Jann Horn at Google Project Zero.

Changes:
 o Allow TXT records on CHAOS qclass.  Used for retriving things like
   version.bind, version.server, authoris.bind, hostname.bind, and id.server.
   [3]

Bug fixes:
 o Fix Windows Unicode incompatibilities with ares_getaddrinfo() [1]
 o Silence false cast-align compiler warnings due to valid casts of
   struct sockaddr to struct sockaddr_in and struct sockaddr_in6.
 o MacOS should use libresolv for retrieving DNS servers, like iOS
 o CMake build system should populate the INCLUDE_DIRECTORIES property of 
   installed targets [2]
 o Correct macros in use for the ares_getaddrinfo.3 man page

Thanks go to these friendly people for their efforts and contributions:
 Brad House (@bradh352), Daniel Stenberg (@bagder), Dmitry Igrishin (@dmitigr),
 Jann Horn, Shelly Vohr, Teemu R (@rytilahti)
 (6 contributors)

References to bug reports and discussions on issues:
 [1] = https://github.com/c-ares/c-ares/pull/328
 [2] = https://github.com/c-ares/c-ares/pull/323
 [3] = https://github.com/c-ares/c-ares/pull/321
