NEXUS-5749: Symptomatic treatment No1

Catch any exception thrown by security related
stuff while gathering the current user ID for
logging purposes (!), to not interrupt
the caller (configuration save) and have
data loss happen.

This is the main symptom we've seen, this
still does not fix the cause, only ensures
that exception seen in issue will not stop
configuration save to happen (that was
caused by rescheduled task).