Added wxTreebook:

- added the control itself
- added protected wxBookCtrlBase::AllowNullPage() to accommodate it
- big changes to the sample to get rid of (most) ugly macros
- added XRC handler for the control
- added docs
- and wxUSE_TREEBOOK everywhere


git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@35862 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

docs/latex/wx/classes.tex

@@ -348,6 +348,8 @@
 \input toolbar.tex
 \input tooltip.tex
 \input tlw.tex
+\input treebook.tex
+\input treebookevent.tex
 \input treectrl.tex
 \input treeevt.tex
 \input treedata.tex