Security update for python3 (moderate)

This update for python3 provides the following fixes:

These security issues were fixed:

• CVE-2018-1061: Prevent catastrophic backtracking in the
  difflib.IS_LINE_JUNK method. An attacker could have used this flaw to
  cause denial of service (bsc#1088004).
• CVE-2018-1060: Prevent catastrophic backtracking in pop3lib’s apop()
  method. An attacker could have used this flaw to cause denial of service
  (bsc#1088009).

These non-security issues were fixed:

• Sort files and directories when creating tarfile archives so that they
  are created in a more predictable way. (bsc#1086001)
• Add -fwrapv to OPTS (bsc#1107030)

This update was imported from the SUSE:SLE-12:Update update project.