Set text label on rnning test and clear log.

HearingTest.py

@@ -113,6 +113,8 @@ class HelloWindow(QMainWindow):
         self.log.append('Key {} pressed at {}'.format(event.key(), time.clock()))
 
     def run_test(self):
+        self.log.setText('')
+        self.title.setText('Test running')
         self.log.append('Starting...')
         self.testing_thread = TestThread(self.library)
         self.testing_thread.played_sound.connect(self.sound_played)
@@ -125,6 +127,7 @@ class HelloWindow(QMainWindow):
 
     def test_finished(self):
         self.test_running = False
+        self.title.setText("Press any key to start...")
         self.log.append('Finished test')