Remove cURL close policy related constants

These options don't do anything and they never have.

Refs:
  http://curl.haxx.se/libcurl/c/curl_easy_setopt.html#CURLOPTCLOSEPOLICY
  http://curl.haxx.se/mail/lib-2006-11/0301.html
Deprecate CN_match in favor of peer_name in SSL contexts
Merge branch 'curlClosePolicy' of https://github.com/DaveRandom/php-src into PHP-5.6

* 'curlClosePolicy' of https://github.com/DaveRandom/php-src:
  Remove cURL close policy related constants