Updated polkit package fixes security vulnerabilities

Local privilege escalation in polkit before 0.113 due to predictable authentication session cookie values (CVE-2015-4625). Various memory corruption vulnerabilities in polkit before 0.113 in the use of the JavaScript interpreter, possibly leading to local privilege escalation (CVE-2015-3256). Memory corruption vulnerability in polkit before 0.113 in handling duplicate action IDs, possibly leading to local privilege escalation (CVE-2015-3255). Denial of service issue in polkit before 0.113 which allowed any local user to crash polkitd (CVE-2015-3218).