Minor stylistic code edits.

justcheckers/app.py

@@ -23,7 +23,6 @@ class MenuScreen(QWidget):
         self.exit_button.clicked.connect(self.exit_app)
 
         widget_layout = QVBoxLayout(self)
-        widget_layout.addWidget(self.systemLabel)
         widget_layout.addStretch()
         widget_layout.addWidget(self.exit_button)
         widget_layout.addStretch()

requirements/development.txt

@@ -1,3 +1,4 @@
 # Requirements for developing the justCheckers app
 Sphinx>=1.2.2
 nose>=1.3.0
+flake8

tasks.py

@@ -18,4 +18,3 @@ def clean():
     """Clean generated files."""
     run('rm *.pyc')
     run('rm _build -rv')
-