added missing iEEGCoordinateSystemDescription, which is an optional field in coordsystem.json

Author: robertoostenveld

validators/schemas/coordsystem_ieeg.json

@@ -3,6 +3,7 @@
         "properties": {
                 "iEEGCoordinateSystem": {"type": "string","minLength": 1},
                 "iEEGCoordinateUnits": {"type": "string","minLength": 1},
+                "iEEGCoordinateSystemDescription": {"type": "string","minLength": 1},
                 "iEEGCoordinateProcessingDescripton": {"type": "string","minLength": 1},
                 "iEEGCoordinateProcessingReference": {"type": "string","minLength": 1},
                 "IntendedFor": {"type": "string","minLength": 1}