Add Airlift JMX modules

[andythsu]

This exposes JMX metrics at /metrics

[Randgalt]

Does this automatically do something? Or is there another PR coming after this?

[andythsu]

Does this automatically do something? Or is there another PR coming after this?

It automatically exposes metrics to /metrics endpoint
The metrics it exposes include (but not limited to)

• http server threads usage
• http client request, response time
• jvm metrics

They come for free from Airlift

We are planning to add some more useful metrics as it fits. For example:

• time it takes to talk to OPA
• time it takes to fetch credentials
• time it takes to sign a request
  ...

These will come in subsequent PRs