Definition: Given a 'poster' sentence and a corresponding 'response' (often, from Facebook or Reddit)classify the sentiment of the given response into four categories: 1) Positive, 2) Negative, 3) Neutral, and 4) Mixed if it contains both positive and negative.
Input: Poster: Senator Durbin spotted his cutest supporter so far. It's a Happy Halloween here at the Fall Faith and Action Event in Chicago  Responser: http://www.midwestenergynews.com/2014/10/16/murky-waters-chicagoans-worry-petcoke-moving-to-barges/
