neverendingreddit - don't kill modal if not exists
modules.neverEndingReddit.getNextPrevLinks returns links or false if none
neverEndingReddit, keyboardNav use modules.neverEndingReddit.nextPrevLinks
to fetch next/prev link elements
de-cruft
neverEndingReddit more tolerant of loading a page with no "next" button
don't show loader widget or attempt to load next page on scroll
NRE "no more posts" message has better calls to action
"couldn't find anything" or "reddit barfed" show the same error
turned 'start from the top', 'try again' links into buttons; added 'random subreddit' button link
Merge pull request #583 from andytuba/nre-fixes

Never ending reddit loads random subreddit.