title: Update not changing visibility in PySimpleGUI
body: <p>I am trying to make a GUI element invisible by using visible=False. It appears that the update function works with every other attribute as well as for values s shown in the code below, except for the <em>visible</em> attribute. Specifically, although the program requests that element (2,2) become invisible, element (4,2) is becoming invisible. Any help with this will be greatly appreciated. Thanks</p>
  
  <pre><code>import PySimpleGUI as sg
  
  layout = [[sg.B(' ', size=(8,4), key=(i,j)) for i in range(0,5)] for j in range(0,4)]
  
  window = sg.Window('Trying to change attribute', layout).Finalize()
  window.Maximize()
  
  while True:             # Event Loop
      event, values = window.read()
      print(event, values)
      window[(1,1)].update(button_color=('blue','yellow'))
      window[(2,2)].update(visible=False)  ## Problem here
      window[(3,3)].update('Hello')
  
      if event in (None, 'Exit'):
          break
      current_marker = window[event].get_text()
  
  </code></pre>