Security update for openvpn (important)

This update for openvpn fixes the following security issues:

• CVE-2017-12166: OpenVPN was vulnerable to a buffer overflow
  vulnerability when key-method 1 is used, possibly resulting in code
  execution. (bsc#1060877).
• CVE-2016-6329: Now show which ciphers should no longer be used in
  openvpn --show-ciphers to avoid the SWEET32 attack (bsc#995374)
• CVE-2017-7478: OpenVPN was vulnerable to unauthenticated Denial of
  Service of server via received large control packet. (bsc#1038709)
• CVE-2017-7479: OpenVPN was vulnerable to reachable assertion when
  packet-ID counter rolls over resulting into Denial of Service of server
  by authenticated attacker. (bsc#1038711)
• Some other hardening fixes have also been applied (bsc#1038713)