Instana

- [AWS Lambda] Reset `requestHasFailed` flag on start of Lambda handler.
- [AWS Lambda] Improve logging for data reporting timeouts.
- [AWS Lambda] Remove misleading "Traces and metrics have been sent to Instana." message.
- Remove deprecated span attributes `span.error` and `span.async`.
- Remove obsolete configuration option `config.agentName`/`INSTANA_AGENT_NAME`.

- [AWS Lambda] Do not try to send data to the Instana back end when a previous request to it has already failed.
- [AWS Lambda] Change span offloading intervall to 5 seconds.
- [AWS Lambda] Make sure that an uninstrumented https connection is used for span offloading.
- [AWS Lambda] Change layer name from `instana` to `instana-nodejs` to prepare for the extension of native AWS Lambda tracing to other runtimes.

- Always capture duration of GraphQL calls.
- Support `INSTANA_DEBUG` in native serverless tracing.

- Do not remove tags from lower priority spans when changing the span type (e.g. http -> graphql)

- Fix mongodb tracing for outdated versions of the mongodb package.

- Support for new website monitoring/mobile back end correlation via extended X-INSTANA-L header.
- Capture request and response headers on outgoing HTTP calls.