Include wx/settings.h according to precompiled headers of wx/wx.h (with other minor cleaning).

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@39310 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

src/html/htmlwin.cpp

@@ -23,13 +23,13 @@
     #include "wx/frame.h"
     #include "wx/dcmemory.h"
     #include "wx/timer.h"
+    #include "wx/settings.h"
 #endif
 
 #include "wx/html/htmlwin.h"
 #include "wx/html/htmlproc.h"
 #include "wx/clipbrd.h"
 #include "wx/dataobj.h"
-#include "wx/settings.h"
 
 #include "wx/arrimpl.cpp"
 #include "wx/listimpl.cpp"