brewでPHP v5.6が入らなかったので対応した．

# brewでPHP v5.6が入らなかったので対応した．
# 最終的にオプションを3つ付けた．

# error
$ brew install josegonzalez/php/php56
> "_TLSv1_2_server_method", referenced from:
> _php_openssl_setup_crypto in xp_ssl.old: symbol(s) not found for architecture x86_64
> clang: error: linker command failed with exit code 1 (use -v to see invocation)
> make: *** [sapi/cgi/php-cgi] Error 1

# error
$ brew install josegonzalez/php/php56 --with-brewed-openssl
> ld: symbol(s) not found for architecture x86_64
> clang: error: linker command failed with exit code 1 (use -v to see invocation)
> make: ** [sapi/fpm/php-fpm] Error 1

# success
$ brew install josegonzalez/php/php56 --with-brewed-openssl --with-homebrew-libressl --with-homebrew-libxml2