* Move OpenSSL functions into a new TlsHelper class
* Add error when sAN certificate cannot be verified due to
CVE-2013-6420
* Throw exception if PHP >= 5.6 manages to use fallback code
* Add support for wildcards in CN/sAN
* Add tests for cert name validation
* Check for backported security fix for CVE-2013-6420 using
testcase from PHP tests.
* Whitelist some disto PHP versions that have the CVE-2013-6420
fix backported.