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

platform/android/api/api.cpp

@@ -30,7 +30,7 @@
 
 #include "api.h"
 
-#include "core/engine.h"
+#include "core/config/engine.h"
 #include "java_class_wrapper.h"
 #include "jni_singleton.h"
 

platform/android/api/java_class_wrapper.h

@@ -31,7 +31,7 @@
 #ifndef JAVA_CLASS_WRAPPER_H
 #define JAVA_CLASS_WRAPPER_H
 
-#include "core/reference.h"
+#include "core/object/reference.h"
 
 #ifdef ANDROID_ENABLED
 #include <android/log.h>

platform/android/api/jni_singleton.h

@@ -31,8 +31,8 @@
 #ifndef JNI_SINGLETON_H
 #define JNI_SINGLETON_H
 
-#include <core/engine.h>
-#include <core/variant.h>
+#include <core/config/engine.h>
+#include <core/variant/variant.h>
 #ifdef ANDROID_ENABLED
 #include <platform/android/jni_utils.h>
 #endif