Added sample showing Alpha drawing for Mac with CoreGraphics

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@41073 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

wxPython/demo/Main.py

@@ -60,6 +60,7 @@ _treeList = [
         'BitmapFromBuffer',
         'RawBitmapAccess',
         'DragScroller',
+        'AlphaDrawing',
         ]),
 
     # managed windows == things with a (optional) caption you can close
@@ -232,6 +233,7 @@ _treeList = [
 
     # Images
     ('Using Images', [
+        'AlphaDrawing',
         'ArtProvider',
         'BitmapFromBuffer',
         'Cursor',
@@ -247,6 +249,7 @@ _treeList = [
 
     # Other stuff
     ('Miscellaneous', [
+        'AlphaDrawing',
         'ColourDB',
         ##'DialogUnits',   # needs more explanations
         'DragScroller',