Major update of all demo programs to use new PEP8 bindings, etc

DemoPrograms old/Demo_OpenCV_Webcam_Minimal.py

@@ -0,0 +1,31 @@
+import PySimpleGUI as sg
+# import PySimpleGUIQt as sg
+# import PySimpleGUIWeb as sg       # has a known flicker problem that's being worked
+import cv2
+
+"""
+    Demo of using OpenCV to show your webcam in a GUI window.
+    This demo will run on tkinter, Qt, and Web(Remi).  The web version flickers at the moment though
+    To exit, right click and choose exit. If on Qt, you'll have to kill the program as there are no right click menus
+    in PySimpleGUIQt (yet).
+"""
+
+sg.ChangeLookAndFeel('Black')
+
+# define the window layout
+layout = [[sg.Image(filename='', key='_IMAGE_', tooltip='Right click for exit menu')],]
+
+# create the window and show it without the plot
+window = sg.Window('Demo Application - OpenCV Integration', layout, location=(800,400),
+                   no_titlebar=True, grab_anywhere=True,
+                   right_click_menu=['&Right', ['E&xit']], )  # if trying Qt, you will need to remove this right click menu
+
+# ---===--- Event LOOP Read and display frames, operate the GUI --- #
+cap = cv2.VideoCapture(0)                               # Setup the OpenCV capture device (webcam)
+while True:
+    event, values = window.Read(timeout=20, timeout_key='timeout')
+    if event in ('Exit', None):
+        break
+    ret, frame = cap.read()                             # Read image from capture device (camera)
+    imgbytes=cv2.imencode('.png', frame)[1].tobytes()   # Convert the image to PNG Bytes
+    window.FindElement('_IMAGE_').Update(data=imgbytes)   # Change the Image Element to show the new image