1. corrected problem with label updating in wxProgressDialog

1. corrected problem with label updating in wxProgressDialog
2. optical fix in wxTipDlg: use wxTE_RICH control to avoid vert scrollbar
3. put wxProgressDialog demo into dialogs sample, seems more appropriate
4. fixed a serious bug in wxProgressDialog when its parent was not a top
   level window (as in controls sample)
5. fixes in BringWindowToTop() usage in msw/dialog.cpp
6. fixed another serious bug in wxProgressDialog::OnClose()
7. wxDialog restores focus to previously focused window once again
8. attempts at fixing wxBusyCursor with modal dialogs problem - unsuccessful

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@6273 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775