Added SetFont to most controls and controls sample

(recompile)
  Added tiny bit of documentation to window.cpp


git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@676 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

include/wx/gtk/font.h

@@ -74,12 +74,8 @@ class wxFont: public wxGDIObject
     bool GetUnderlined(void) const;
 
     wxFont( char *xFontName );
-    
-  private:
-  
-    friend wxDC;
-    friend wxPaintDC;
-    friend wxWindow;
+
+  // implementation        
     
     GdkFont* GetInternalFont(float scale = 1.0) const;