Adds explicit status code 303 redirect to catalog#update

The redirect called in the catalog#update method is defaulting to a 302 redirect: http://api.rubyonrails.org/classes/ActionController/Redirecting.html#method-i-redirect_to

302's are notoriously non-SEO friendly... I initially thought a 301 redirect would create a more crawl-able results page but after some research I believe the best way to do this is with a 303 redirect? 

Proposed workflow: user clicks resource title which initiates a POST request with the counter data, then the 303 redirect results in a GET request to the requested resource... this seems to be the most logical flow.. I don't think it should be a 302 because the resource SHOULD be cached, i.e. although there is a form being posted it isn't changing the expected resource result.