tests: Add test script and fix pep8 in unittest.

src/Model/test_Model.py

@@ -24,6 +24,7 @@ from Model.Saved import SavedStatus
 from Model.Study import Study
 from Model.River import River
 
+
 class StudyTestCase(unittest.TestCase):
     def test_create_study(self):
         study = Study.new("foo", "bar")
@@ -57,6 +58,7 @@ class StudyTestCase(unittest.TestCase):
         study = Study.new("foo", "bar")
         self.assertNotEqual(study.river, None)
 
+
 class RiverTestCase(unittest.TestCase):
     def test_create_river(self):
         status = SavedStatus()