GDA-5554 introduce a new preference so the Command Queue will now only
disable/enable the JythonTerminalView's toolbar buttons if the
preference is set to true.

So this reverts back to the previous functionality and now beamlines
have to enable the preference to disable/enable the buttons based on the
Command Queue status.
Merge branch 'master' of ssh://dascgitolite@dasc-git.diamond.ac.uk/gda/gda-core.git
Merge branch 'master' of ssh://dascgitolite@dasc-git.diamond.ac.uk/gda/gda-core.git
Merge branch 'master' of ssh://dascgitolite@dasc-git.diamond.ac.uk/gda/gda-core.git