most commented improvements

[giuse]

1) It would be fine to have ordering of most commented items based on date, i.e. when having items that have the same number of comments, order them by descending date of the comment to avoid not to list a recent article that had the same number of comment than an old one (having a limit of number of item to be displayed).
2) add the option to display the date of the last comment (with some format different than the title of the item)
cheers

Giuse