MFH: r489635

Update 1.15.4 --> 1.15.5

Major changes in 1.15.5 (2019-01-07)

This is a bug fix release.

• Fix a regression in the MEMORY credential cache type which could cause client programs to crash.

• MEMORY credential caches will not be listed in the global collection, with the exception of the default credential cache if it is of type MEMORY.

• Remove an incorrect assertion in the KDC which could be used to cause a crash [CVE-2018-20217].

Approved by: portmgr (miwi)