OverlayInput: get MaxNbFilesToGet option from any level in overlay hierarchy
BEGINRELEASENOTES
*Workflow
CHANGE: MaxNbFilesToGet can now be set at any level of the Overlay hierarchy
*Core
NEW: New utility for Configuration: :func:~ILCDIRAC.Core.Utilities.Configuration.getOptionValue
to get option from any level of given path in Configuration
ENDRELEASENOTES