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: Congratulations to the new citizens of #CT & the #USA taking the oath at today's naturalization ceremonies  Responser: http://www.facebook.com/notes/articlevorg/re-citizens-united-ruling-solutions-lawrence-lessigs-recent-testimony-in-committ/507872265890047
