Reorganized core/ directory, it was too fatty already

-Removed FuncRef, since Callable makes it obsolete
-Removed int_types.h as its obsolete in c++11+
-Changed color names code

core/math/quick_hull.cpp

@@ -30,7 +30,7 @@
 
 #include "quick_hull.h"
 
-#include "core/map.h"
+#include "core/templates/map.h"
 
 uint32_t QuickHull::debug_stop_after = 0xFFFFFFFF;