ListDir

'ListDir': scan the structure of the directory tree (for dataview.m)
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 function [ListDevices,ListRecords,ListXml,List]=ListDir(CurrentPath,ListExperiments,ListDevices_in,ListRecords_in)

 
 OUTPUT:
 ListDevices: list of Devices 
 ListRecords: list of records
 ListXml: list of xml file names
 List: structure representing the tree structure

INPUT
 CurrentPath: full name (including path) to the input campaign (or subcampaign), we assume that
          data are organised as (sub)campaign/Experiment/Device/(Record/)/file .xml
 ListExperiments: list of experiments to scan (cell of names)
 ListDevices_in: list of devices to scan (cell of names)
 ListRecords_in: list of records to scan (cell of names)