adds a test

photograb/test/test_config.py

@@ -60,4 +60,6 @@ class TestParseConfig(unittest.TestCase):
         raise NotImplementedError
 
     def test_asserts_camera_path_is_present(self):
-        pass
+        self.test_config.remove_option('DEFAULT', 'camera')
+        with self.assertRaises(BadConfiguration, msg="No camera path set !"):
+            parse_config(self.test_config)