Moved logic for versioned clients from AWS::DynamoDB::Client to AWS::Core::Client.
Minimal refactor so services support versioned clients.
Removed duplicate code from DynamoDB::Client.
Updated to the 2013-05-12 API version for AWS::CloudFront::Client.
Updated AWS::RDS::Client to the latest API version.
Merge pull request #303 from aws/api-versions

Add suport for multiple API versions to every service client
Merge branch 'cloudfront-update'
Merge branch 'rds-update'
Bumped EC2 API version in the client class.
Updated RDS client spec for the new api version.
Bumped CloudFront API client.
Fix typo in SimpleEmailService::Identity
Merge pull request #305 from kdayton-/typo_fix

Fix typo in SimpleEmailService::Identity
Ignore some Gemfile groups in Travis tests.
Update docs.rake