Node.js agent v5.3.0

Added span_events and transaction_segments attribute destinations.
Span event and segment attributes can now be filtered using the same include/exclude config rules as other types. See agent attribute configuration for more details.
Added metadata field to connect payload, for collecting NEW_RELIC_METADATA_-prefixed environment variables.
Added DynamoDB to datastores.
Added opaque option to datastore operation spec.
Added Kubernetes utilization detection.
Upgraded concat-stream and readable-stream to next major version.
These modules had previously been held back due to support for Node <6. Since v5.0.0 we dropped that support thus enabling these updates.
Added SQS as a supported messaging library name.
Enabled tracking of callback via message-shim.recordConsume when no messageHandler provided.

The agent will now consistently harvest in all response cases when in serverless mode.
Previously, the agent's harvest was in a race with process suspension in the event of an uncaught exception, or responding without calling a callback. A synchronous harvesting process is now used to circumvent this racing issue.
Fixed issue with socket connection errors causing the agent to stop attempting to connect at startup.
Fixed opaque segment functionality for message-shim.recordProduce.
Fixed opaque segment functionality for message-shim.recordConsume.