* Move async strategies to annotation support
* Fix dependencies and refactor copypasta
* Move AsyncSpanEndStrategy to annotation support project
* spotless
* Port RxJava 2 async strategy to new interface
* Port RxJava 3 async strategy to new interface
* Port Guava async strategy to new interface
* Port Reactor async strategy to new interface
* Kick CI
* Add Guava instrumentation library with AsyncSpanEndStrategy
* Enable span strategy in advice
* Spotless
* Nix attempt at typeInitializer advice, leave TODO comment to revisit
* Move async span strategy registration to helper class
* Remove use of sameThreadExecutor
* Make helper class final and add comment about relying on static initializer