update CHANGELOG for 0.7.1
update CHANGELOG for 0.7.1

stipple/cassandra_new,rightscale/cassandra,cassandra-rb/cassandra,stipple/cassandra_new,cassandra-rb/cassandra,rightscale/cassandra,cassandra-rb/cassandra,rightscale/cassandra,cassandra-rb/cassandra,stipple/cassandra_new,stipple/cassandra_new