Fix a couple of Impress load/reload bugs

openlp/plugins/presentations/lib/messagelistener.py

@@ -74,7 +74,6 @@ class MessageListener(object):
             return
         if not self.controller.is_loaded():
             self.controller.load_presentation(self.controller.filepath)
-        else:
         self.controller.start_presentation()
         if self.controller.slidenumber > 1:
             self.controller.goto_slide(self.controller.slidenumber)

openlp/plugins/presentations/lib/presentationcontroller.py

@@ -198,6 +198,8 @@ class PresentationController(object):
         recent than the powerpoint
         """
         lastimage = self.get_slide_preview_file(self.get_slide_count())
+        if lastimage is None:
+            return False
         if not os.path.isfile(lastimage):
             return False
         imgdate = os.stat(lastimage).st_mtime