New keys matching amazon-kinesis-client 1.1.0

Added config keys region-name and validate-sequence-number-before-checkpointing, which were added to amazon-kinesis-client 1.1.0 in commit: https://github.com/awslabs/amazon-kinesis-client/commit/13aad26a801850daf76f711b4d17bf80a4ea181e
Merge pull request #68 from ulsa/patch-1

New keys matching amazon-kinesis-client 1.1.0