[poincare] Engine-->Helper and break LayoutHelper into LayoutHelper and

SerializationHelper

apps/solver/equation_models_parameter_controller.cpp

@@ -2,7 +2,7 @@
 #include "list_controller.h"
 #include "../constant.h"
 #include <assert.h>
-#include <poincare/layout_engine.h>
+#include <poincare/layout_helper.h>
 #include "../i18n.h"
 
 using namespace Poincare;