Define the repository scope

[trask]

This is an attempt to define the scope of this repository, mostly in relation to https://github.com/open-telemetry/opentelemetry-java, in order to help things to go to the right place.

If this scope is agreed upon, we can move https://github.com/open-telemetry/opentelemetry-java/tree/master/extensions/runtime_metrics over to this repository, and delete https://github.com/open-telemetry/opentelemetry-java/tree/master/extensions/logging/log4j2_extensions which was accidentally re-implemented in this repository (#735).

cc: @open-telemetry/java-approvers

Will wait for @jkwatson (back Jul 30) before making any decisions here, just want to get the ball rolling and hear any initial comments / feedback.

[anuraaga]

Suggested change

	* Spring integrations
	* Framework integrations (e.g., Spring)

Honestly nothing comes to mind but there must be more frameworks than just Spring right? :D

[iNikem]

E.g. Ratpack, Play :)

[trask]

I think frameworks are covered under Instrumentation bullet above. Narrowed this down to Spring Boot starters for now(?)

[trask]

One thing I didn't include, because I think may make more sense in SDK repo:

• Integrations with other telemetry libraries, e.g.
  • OpenTracing
  • Micrometer
  • Spring Cloud Sleuth / Brave

but we can discuss also

[trask]

Discussed with opentelemetry-java maintainers on Fri, and have agreement on this initial scope