Update for play site changes

* App pages changed: fix youtube_video_ids and rating_distribution
update test pages and the test expectations to pass w/new test
pages

* fix leaderboard scraping and tests
the leaderboard page changed and this updates the scraping to
work.  It also updates the pages used for the tests to newer
versions.

* the Rakefile is updated to fetch the leaderboards of the actual
category, since the tests pretend the data is for the ARCADE
category.