SCATTER-147

avoid too much processing in Java (that's the reason for haing a database)

This will also return the latest commissioning visit for staff
(in case defVisit isn't up to date)
GDA-5657 stops oarcle's interest in a set timezone

Conflicts:
	uk.ac.gda.core/src/gda/data/metadata/icat/DLSIcat.java
improve messages to user and prevent errors when shutting down a
pipeline already shutdown
Merge remote-tracking branch 'origin/8.30.prod' into 8.30
Merge branch '8.30' of ssh://dascgitolite@dasc-git.diamond.ac.uk/gda/gda-core.git into 8.30
Merge remote-tracking branch 'origin/8.30'

Conflicts:
	uk.ac.gda.core/src/gda/data/metadata/icat/DLSdicat.java
	uk.ac.gda.core/src/gda/data/scan/datawriter/NexusDataWriter.java