[statistic] support grabbing the correct statistic
[statistic] fixed statistics for elb
[statistic] fixed statistics for ec2
[statistic] fixed statistics for ebs
[statistic] fixed statistics for rds
[statistic] fixed statistics for sns
[statistic] fixed statistics for sqs
[statistic] fixed statistics for ec
[statistic] fixed statistics for ddb (WIP)
Merge pull request #13 from newrelic-platform/statistic

Fix statistic used for certain metrics