Add GetNormal to Triangle

Source/Engine/Core/Math/Triangle.h

@@ -49,6 +49,13 @@ public:
     {
     }
 
+public:
+
+    Vector3 GetNormal() const
+    {
+        return Vector3::Normalize((V1 - V0) ^ (V2 - V0));
+    }
+
 public:
 
     // Determines if there is an intersection between the current object and a Ray