Jaeger: Enable configuration via MP config

[objectiser]

Currently the Jaeger tracer is configured using system properties or environment variables.

We should also enable the tracer to be configured using MP config.

To support both configuration approaches, and avoid having to programmatically create the different components of the tracer (using the builders), it may be best to copy the MP config values into system properties prior to creating the tracer (fromEnv()). The only issue is deciding which values take precedence when both are defined?