patch from Dimitri fixing a few memory leaks and unTABbing the sources

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@14660 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

samples/treelay/treelay.cpp

@@ -24,7 +24,7 @@
 
 #include "treelay.h"
 
-wxTreeLayoutStored *myTree = NULL;
+wxTreeLayoutStored *myTree = (wxTreeLayoutStored *) NULL;
 
 // A macro needed for some compilers (AIX) that need 'main' to be defined
 // in the application itself.
@@ -85,6 +85,17 @@ bool MyApp::OnInit()
   return TRUE;
 }
 
+int MyApp::OnExit()
+{
+    if (myTree)
+    {
+        delete myTree;
+        myTree = (wxTreeLayoutStored *) NULL;
+    }
+
+    return 0;
+}
+
 void MyApp::TreeTest(wxTreeLayoutStored& tree, wxDC& dc)
 {
   tree.Initialize(200);