Some artifacts missing `NOTICE`, `LICENSE` files

Looks like necessary `LICENSE` and `NOTICE` files are not copied from main level to artifacts other than `jr-objects` (and due to that, `jr-all`). These need to be added to:

* `jr-annotation-support`
* `jr-retrofit2`
* `jr-stree`

Although we are not necessarily publishing new releases from branches pre-2.14, let's fix this for 2.12 branch upwards, just in case.
