Updated to reflect pricing announcement on 2013-01-31

Ref: http://aws.amazon.com/about-aws/whats-new/2013/01/31/amazon-ec2-price-reduc-m3-global-data-transfer-drop/
Ref: http://aws.amazon.com/ec2/pricing/
Merge pull request #26 from miketheman/updated_pricing

Updated to reflect pricing announcement on 2013-01-31