Add Python snippets for the BitmapBundle docs

docs/sphinx/rest_substitutions/snippets/python/converted/wx.BitmapBundle.1.py

@@ -0,0 +1,8 @@
+
+        # In __init__ for a wx.Frame
+        ...
+        toolBar = self.CreateToolBar()
+        bitmaps = [ wx.Bitmap('open_32x32.png'),
+                    wx.Bitmap('open_32x32.png'),
+                    wx.Bitmap('open_32x32.png') ]
+        toolBar.AddTool(wx.ID_OPEN, wx.BitmapBundle.FromBitmaps(bitmaps))

docs/sphinx/rest_substitutions/snippets/python/converted/wx.BitmapBundle.2.py

@@ -0,0 +1,2 @@
+
+    # RC resources are not supported in wxPython

docs/sphinx/rest_substitutions/snippets/python/converted/wx.BitmapBundleImpl.1.py

@@ -0,0 +1,25 @@
+
+        class MyCustomBitmapBundleImpl(wx.BitmapBundleImpl):
+            def __init__(self):
+                super().__init__()
+                self.img = wx.Image(pngFile)
+                self.size = self.img.GetSize()
+
+            def GetDefaultSize(self):
+                # Report the best or default size for the bitmap
+                return self.size
+
+            def GetPreferredBitmapSizeAtScale(self, scale):
+                # Return the size of the bitmap at the given display scale. It
+                # doesn't need to be size*scale if there are unscaled bitmaps
+                # near that size.
+                return self.size * scale
+
+            def GetBitmap(self, size):
+                # Return the version of the bitmap at the desired size
+                img = self.img.Scale(size.width, size.height)
+                return wx.Bitmap(img)
+
+
+
+    toolBar.AddTool(wx.ID_OPEN, wx.BitmapBundle.FromImpl(MyCustomBitmapBundleImpl())