Moved all demo programs into subfolder

DemoPrograms/Demo_Window_Disappear.py

@@ -0,0 +1,21 @@
+#!/usr/bin/env python
+import sys
+if sys.version_info[0] >= 3:
+    import PySimpleGUI as sg
+else:
+    import PySimpleGUI27 as sg
+
+layout = [[ sg.Text('My Window') ],
+          [ sg.Button('Disappear')]]
+
+window = sg.Window('My window').Layout(layout)
+
+while True:
+    event, values = window.Read()
+    if event is None:
+        break
+    if event == 'Disappear':
+        window.Disappear()
+        sg.Popup('Click OK to make window reappear')
+        window.Reappear()
+