Support tagging EC2 resources

Amazon now allows tagging EC2 resources with key/value metadata. As soon as Boto supports this we should update the internals to allow tags instead of using security groups to organize instances. This will also be great for organizing EBS volumes! Finally Amazon!

More info on tagging: http://docs.amazonwebservices.com/AWSEC2/latest/UserGuide/Using_Tags.html

Looks like Boto is handling this now according to this http://github.com/boto/boto/issues#issue/6

Need to pull down the project and see how it works.