Update copyright year in NOTICE to 2014

Author: Matei Zaharia <matei@databricks.com>

Closes #174 from mateiz/update-notice and squashes the following commits:

47fc1a5 [Matei Zaharia] Update copyright year in NOTICE to 2014

NOTICE

 Apache Spark
-Copyright 2013 The Apache Software Foundation.
+Copyright 2014 The Apache Software Foundation.
 
 This product includes software developed at
 The Apache Software Foundation (http://www.apache.org/).