Replaced old wxSizer,

Converted two of wxGTK's standard dialogs to use them,
  Applied two fixes to wxDC code,
  Made wxRadiobox a little smaller,
  Added sizer.h to wx.h


git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@3325 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

src/gtk1/radiobox.cpp

@@ -271,7 +271,7 @@ wxSize wxRadioBox::LayoutItems()
             node = node->Next();
         }
         res.x = x+4;
-        res.y = 42;
+        res.y = 40;
     }
 
     return res;