DynamoDB support

I made a module for AWS DynamoDB

I hope it can become a part of queryDSL


All tests pass fine when using AWS DynamoDB, but when running local using alternator a few fail due an alternator limitation:
https://github.com/mboudreau/Alternator/issues/80

To run tests on dynamo is necessary an AWS account and to configure aws.secretKey and aws.accessKeyId on System properties.