uimenu properties are not up to date
@sgougeon)
Reported by Samuel GOUGEON (BUG DESCRIPTION:
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The list of uimenu properties is not up to date:
Children, Handle_visible, callback_type, and user_data properties are not listed and described.
HOW TO REPRODUCE THE BUG:
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uimenu(gcf(),'label', 'Test')
https://help.scilab.org/docs/6.0.2/en_US/uimenu_properties.html