Retraction of NXevent_data_em_set for the reason that just an additional grouping in an appdef can also be achieved by just adding event_data_set(NXobject) and having current NXevent_data_em_set docstring there inside the appdef

Author: atomprobe-tc

base_classes/NXevent_data_em.nxdl.xml

@@ -33,6 +33,12 @@
          bring the microscope into a state where conditions are considered better
          or of whatever high enough quality for continuing the measurement.
 
+         Which temporal granularity is adequate depends on the situation and
+         research question. Using a model which enables a collection of events offers
+         the most flexible way to cater for both experiments with controlled electron
+         beams in a real microscope or the simulation of such experiments or
+         individual aspects of such experiments.
+         
          In all these use cases in practice it would be useful to have a mechanism
          whereby time-dependent data of the instrument state can be stored and
          documented with an interoperable representation. Indeed, how a session on an