Add support for point light and materials.

Add material to objects.

tests/light_test.cpp

@@ -0,0 +1,24 @@
+/*
+ *  DoRayMe - a quick and dirty Raytracer
+ *  Light unit tests
+ *
+ *  Created by Manoël Trapier
+ *  Copyright (c) 2020 986-Studio.
+ *
+ */
+#include <light.h>
+#include <math.h>
+#include <colour.h>
+#include <tuple.h>
+#include <gtest/gtest.h>
+
+TEST(LightTest, A_point_lighthas_a_position_and_intensity)
+{
+    Colour intensity = Colour(1, 1, 1);
+    Point position = Point(0, 0, 0);
+
+    Light light = Light(POINT_LIGHT, position, intensity);
+
+    ASSERT_EQ(light.position, position);
+    ASSERT_EQ(light.intensity, intensity);
+}