Document multiple security issues of PHP 5.6

Security: CVE-2016-7416
Security: CVE-2016-7412
Security: CVE-2016-7414
Security: CVE-2016-7417
Security: CVE-2016-7411
Security: CVE-2016-7413
Security: CVE-2016-7418
Security: https://vuxml.freebsd.org/freebsd/8d5180a6-86fe-11e6-8d93-00248c0c745d.html

Approved by: pi (mentor)