meta: add fwd.hpp (see #735)

src/entt/fwd.hpp

@@ -1,5 +1,6 @@
 #include "core/fwd.hpp"
 #include "entity/fwd.hpp"
+#include "meta/fwd.hpp"
 #include "poly/fwd.hpp"
 #include "resource/fwd.hpp"
 #include "signal/fwd.hpp"

src/entt/meta/fwd.hpp

@@ -0,0 +1,38 @@
+#ifndef ENTT_META_FWD_HPP
+#define ENTT_META_FWD_HPP
+
+
+namespace entt {
+
+
+class meta_sequence_container;
+
+
+class meta_associative_container;
+
+
+class meta_any;
+
+
+struct meta_handle;
+
+
+struct meta_prop;
+
+
+struct meta_ctor;
+
+
+struct meta_data;
+
+
+struct meta_func;
+
+
+class meta_type;
+
+
+}
+
+
+#endif