Support using the Agent as a layer on AWS Lambda

When adding the AWS X-Ray Java Agent to a Lambda function via a layer it causes cold starts to be much (30+ seconds) slower. This increase is so dramatic that it is a blocker for having official Lambda support. This is a result of the initialization work the agent must do to auto-instrument your Lambda code, and appears to be a problem with all auto-instrumentation java agents on the Lambda platform. An investigation is needed with the Lambda team to resolve this.