favorites feature fix

The favorites feature is broken.

The first time you try to add to favorites in a fresh installation of the plugin the AddVideoToFavorites function will fail because the PCbfFavorites data storage doesn't exists yet so you get a channel is not responding error and the videoclip is not added to favorites.

Another problem is that the object container when showing the VideoClipObject which shows the Add to Favorites or Remove from Favorites link should not be cached or otherwise it shows incorrect link the second time you visit that clip after adding or removing from favorites. After you add the clip it will continue showing Add to Favorites if it is cached when it should start showing Remove from Favorites instead. And vice versa.

Both problems are solved in this patch.