underlying C++ object deleted

[Lee Braiden]

This doesn't seem to do any harm, and might be just a garbage collection issue, but occasionally, KatchTV gives this traceback on shutdown:

Exception in thread Thread-1:
Traceback (most recent call last):
  File "threading.py", line 460, in __bootstrap
    self.run()
  File "/usr/lib/katchtv/code/thirdparty/ThreadPool.py", line 173, in run
    callback(cmd(**kwArgs))
  File "/usr/lib/katchtv/code/TaskPool.py", line 32, in __call__
    self.__obj.finished()
  File "/usr/lib/katchtv/code/utils.py", line 465, in newFunction
    return f(*args, **kw)
  File "/usr/lib/katchtv/code/KTVBookmarksListView.py", line 61, in finished
    listviewitem = self.__bookmarksView.getItemForFeed(feed)
  File "/usr/lib/katchtv/code/utils.py", line 465, in newFunction
    return f(*args, **kw)
  File "/usr/lib/katchtv/code/KTVBookmarksListView.py", line 253, in getItemForFeed
    return self.getItemForURI(feed.uri())
  File "/usr/lib/katchtv/code/utils.py", line 465, in newFunction
    return f(*args, **kw)
  File "/usr/lib/katchtv/code/KTVBookmarksListView.py", line 259, in getItemForURI
    item = self.allChannelsBMark.firstChild()
RuntimeError: underlying C/C++ object has been deleted

Seems easiest to catch if you close the app soon after opening. Probably because it's updating feeds just then, and other threads are trying to use the deleted object.