[ue4] Fix private include in SpineWidget.h. Closes #1538.

spine-ue4/Plugins/SpinePlugin/Source/SpinePlugin/Public/SpineWidget.h

@@ -29,11 +29,10 @@
 
 #pragma once
 
-#include "SpinePluginPrivatePCH.h"
-
 #include "Runtime/UMG/Public/UMG.h"
 #include "Runtime/UMG/Public/UMGStyle.h"
-
+#include "SpineSkeletonDataAsset.h"
+#include "spine/spine.h"
 #include "SpineWidget.generated.h"
 
 class SSpineWidget;