Added mtk_tga Unit Test to makefile

Makefile

 
 #################################################################
 
+TGA.test:
+	mkdir -p $(BUILD_TEST_DIR)
+	$(CC) $(TEST_FLAGS) -D__TEST_ \
+		src/mtk_tga.cpp -o $(BUILD_TEST_DIR)/TGA.test
+
+#################################################################
+

src/mtk_tga.cpp

     if (!mtk_image__tga_check(f))
     {
       if (!mtk_image__tga_load(f, &image, &width, &height, &type))
-	delete [] image;
+      {
+        printf("Loaded %s successfully!\n", argv[1]);
+        delete [] image;
+      }
     }
 
     fclose(f);
+  } else {
+      printf("Usage: %s testfile.tga\n", argv[0]);
   }
 
   return 0;