merge of RTL changes (with many modifications) from SOC2006_RTL branch

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@40994 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

include/wx/gtk/window.h

@@ -113,6 +113,9 @@ public:
     virtual void AddChild( wxWindowBase *child );
     virtual void RemoveChild( wxWindowBase *child );
 
+    virtual void SetLayoutDirection(wxLayoutDirection dir);
+    virtual wxLayoutDirection GetLayoutDirection() const;
+
     // currently wxGTK2-only
     void SetDoubleBuffered(bool on);
 
@@ -172,6 +175,10 @@ public:
     // base version just does GetEventHandler()->ProcessEvent()
     virtual bool GTKProcessEvent(wxEvent& event) const;
 
+    // Map GTK widget direction of the given widget to/from wxLayoutDirection
+    static wxLayoutDirection GTKGetLayout(GtkWidget *widget);
+    static void GTKSetLayout(GtkWidget *widget, wxLayoutDirection dir);
+
 protected:
     // Override GTKWidgetNeedsMnemonic and return true if your
     // needs to set its mnemonic widget, such as for a