Update feedlist.js: skip on_catchup_show_next_feed for "All articles" and "Fresh articles"

The option on_catchup_show_next_feed is buggy for "All articles" (feed ID == -4) and "Fresh articles" (feed ID == -3), as it tries to jump to the next feed with unread articles, while in the process of marking all articles read.
Also, I believe it makes sense to just stay in "All articles" or "Fresh articles" after hitting "Mark as read", independently of the option "on_catchup_show_next_feed".
Therefore, I suggest just skipping "on_catchup_show_next_feed" when feed ID is smaller or equal than -3.