def promote_keys( data )
      data.keys.select{|k| k.start_with?('_') }.each do |key|
        data[key.sub(/^_/,'')] = data[key]
        data = data.delete(key).merge(data)
      end

      data
    end
def promote_keys( data )
      data.keys.select{|k| k.start_with?('_') }.each do |key|
        data[key.sub(/^_/,'')] = data[key]
        data = data.delete(key).merge(data)
      end

      data
    end
If underscore keys, copy children to top level vars too
 Input:
   _colors:
     yellow: '#fco'
 Output:
   colors: { yellow: '#fco' }
   yellow: '#fco'