Outsourced GsweMoonPhaseData to its own sources

This messed up documentation, still checking why

src/gswe-moment.h

@@ -21,6 +21,8 @@
 #include <glib-object.h>
 
 #include "gswe-timestamp.h"
+#include "gswe-moon-phase-data.h"
+#include "gswe-types.h"
 
 #define GSWE_TYPE_MOMENT            (gswe_moment_get_type())
 #define GSWE_MOMENT(obj)            (G_TYPE_CHECK_INSTANCE_CAST((obj), GSWE_TYPE_MOMENT, GsweMoment))