Make sure folder is stable before we get articles

Might solve issue #285
Move some logic to ArticleController (fits better)
Make UnifiedDisplayView refreshes more pleasant.

No need to refresh current folder at the end of the refresh queue, since it is already refreshed when the current folder has finished being refreshed, thanks to the MA_Notify_ArticleListStateChange notification
Memory management improvements

Make sure objects added to NSMutableArray’s and NSMutableDictionary’s are autoreleased before being added
Change dict & array properties to copy instead of retain

To limit risks of objects being cyclically retained
Simplify WebFrame parameter management

No need to pass a newly allocated & retained string to the WebFrame
Fix the UnifiedDisplayView responder