#5 play with CocoaLumberjack
#5 notify main thread when a chunk of file items are added
#5 reload table when chunks are added
#5 fix parent path finding
#5 add rudimentary filtering
#5 add rudimentary filtering II
#5 make open quickly window wider
 #5 use operation queues

- wait more often
- cancel more often
#5 synchronize some operations
#5 when open quickly ends, wait until all operations cancels and tidy up arrays
#5 traverse when setting the target url and remove all children items before caching
#5 cancel operations when resetting open quickly window
#5 do not wait until operations are finished
#5 add rudimentary progress indicator