Added tox configuration

... and fixed pep8 warnings. There's a lot of them that are still
ignored, but that's because it's too much of a step to take at once.

core/gui/base.py

@@ -1,31 +1,30 @@
 # Created By: Virgil Dupras
 # Created On: 2010-02-06
 # Copyright 2014 Hardcoded Software (http://www.hardcoded.net)
-# 
-# This software is licensed under the "BSD" License as described in the "LICENSE" file, 
-# which should be included with this package. The terms are also available at 
+#
+# This software is licensed under the "BSD" License as described in the "LICENSE" file,
+# which should be included with this package. The terms are also available at
 # http://www.hardcoded.net/licenses/bsd_license
 
 from hscommon.notify import Listener
-from hscommon.gui.base import NoopGUI
 
 class DupeGuruGUIObject(Listener):
     def __init__(self, app):
         Listener.__init__(self, app)
         self.app = app
-    
+
     def directories_changed(self):
         pass
-    
+
     def dupes_selected(self):
         pass
-    
+
     def marking_changed(self):
         pass
-    
+
     def results_changed(self):
         pass
-    
+
     def results_changed_but_keep_selection(self):
         pass
-    
+