=per #15516 correct tell_commandPersist_reply test with right props
Merge pull request #15517 from hepin1989/#15516-current-persistentActorBenchmark-props

=per #15516 correct tell_commandPersist_reply test with right props
=act fixed typo in scaladoc, and => an

Thanks @geoffjentry for spotting this :-)
Merge pull request #15522 from ktoso/act-simple-typo-ktoso

=act fixed typo in scaladoc, and => an (for Validation)
=doc #15207 add note about UndeclaredThrowableException when used from Java
+tes #12681 add EchoActor
Merge pull request #15525 from 2m/wip-15207-timeoutexception-clarification

=doc #15207 add note about UndeclaredThrowableException when used from Java (validation)
+per #13815 akka-persistence-tck based on @krasserm's work

Original here: https://github.com/krasserm/akka-persistence-testkit

New features:
* merged martin's tests
* usable from java (junit 4)
* simple bench test, which helps checking if ordering is perserved under
  bigger workloads and simple perf checking
* does NOT include tests for already deprecated features (deleteMessages)
* docs

Resolves #13815
Merge pull request #15514 from ktoso/wip-13815-persistence-TCK-ktoso

+per #13815 akka-persistence-tck based on @krasserm's work
Merge pull request #15526 from ktoso/port-tes-echoactor-ktoso

+tes #12681 add EchoActor (for Validation)
=ben #15520 update persistence benchmark to be more relevant

Thanks @hepin1989 for noticing it got outdated a bit.

Resolves #15520