Add kafka extension to agent

[kford-newrelic]

Description

Add existing kafka  extension to the agent such that additional metrics are reported (see also this PoC). 

Acceptance Criteria

• clientId is reported for all metrics, allowing us to query metrics for specific clients
• Per-topic and per-node metrics are reported by default. (As of release 2.1.1, you can disable per-topic metrics by setting kafka.metrics.topic.metrics.disabled: true and disable per-node metrics by setting kafka.metrics.node.metrics.disabled: true in the agent config. The environment variable equivalents are NEW_RELIC_KAFKA_METRICS_TOPIC_METRICS_DISABLED and NEW_RELIC_KAFKA_METRICS_NODE_METRICS_DISABLED)
• The client version is reported as a gauge by default
• counter metrics are reported as deltas of total values which allows "natural" bucketing of rates in NRQL. The more popular rate gauges we typically use are bucketed on the Kafka/client side.
• Requests to seed brokers and group coordinators are called out clearly and (in the case of group coordinators) node IDs properly identified.
• The structure of the metric namespace has been redesigned to play nice with NRQL semantics for timeslice queries. We currently use custom metrics.
• The Kafka APM Nerdlet will automatically display Kafka metrics generated by this agent extension, giving service owners Kafka metrics "for free".
• Events are produced describing per-clientId configuration to unambiguously identify the effective configuration
• Report (and allow faceting by) partitionId (NEWRELIC-343)
• Report (and allow faceting by) topicId (NEWRELIC-3246)

Design Consideration/Limitations

Note that this extension could result in high overhead, so users should be able to configure whether this functionality is enabled (it should be disabled by default)

Dependencies

N/A

Additional context

N/A

[workato-integration]

https://issues.newrelic.com/browse/NEWRELIC-9450