Couple of small optimisation

Add option to build for gprof
Do not build by default with the renderstat (they have a reasonable impact on performances)
Separated created ray and castedray in the stats
Trying to force some simple function to be inlined

tests/christmasball_render.cpp

@@ -229,13 +229,14 @@ int main()
     w.addObject(s);
 
     /* ----------------------------- */
-
+    /*
     FILE *fpOut = fopen("christmas_worlddump.json", "wt");
     if (fpOut)
     {
         w.dumpMe(fpOut);
         fclose(fpOut);
     }
+    */
     /* ----------------------------- */
 
 

tests/dragon_scene.cpp

@@ -117,14 +117,7 @@ int main()
     w.addObject(dragon);
 
     /* ----------------------------- */
-/*
-    FILE *fpOut = fopen("dragon_worlddump.json", "wt");
-    if (fpOut)
-    {
-        w.dumpMe(fpOut);
-        fclose(fpOut);
-    }
-*/
+
     OctreeOptimisation opt;
     w.finalise(opt);