Trying to speed compilation a bit

direct/src/interval/interval_composite1.cxx

@@ -0,0 +1,10 @@
+#include "config_interval.cxx"
+#include "cInterval.cxx"
+#include "cIntervalManager.cxx"
+#include "cLerpInterval.cxx"
+#include "cLerpNodePathInterval.cxx"
+#include "cLerpAnimEffectInterval.cxx"
+#include "cMetaInterval.cxx"
+#include "hideInterval.cxx"
+#include "showInterval.cxx"
+#include "waitInterval.cxx"