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)
=sam #12702 Create FsmSimpleRedelivery sample

This one is created instead of the batching pattern of #12702, as suggested by @ktoso in #12702's discussion.
=ben #15520 update persistence benchmark to be more relevant

Thanks @hepin1989 for noticing it got outdated a bit.

Resolves #15520
Merge pull request #15536 from ktoso/ben-updatePersistenceBench-ktoso

=ben #15520 update persistence benchmark to be more relevant
=per do not run perf spec on jenkins, just validate compilation
Merge pull request #15539 from ktoso/per-increase-timeout-on-measurement-spec-ktoso

=per do not run perf spec on jenkins, just validate compilation
+doc #15537 add Typed router pattern
Merge pull request #15540 from ktoso/doc-typed-router-ktoso

+doc #15537 add Typed Router pattern
=act #15488 Removed guard around _logLevel

This patch removes a lock around the getter of _logLevel. The setter is
still guarded for consistency. Note that out of thin-air reads, while
not excluded under the current JMM, are forbidden by current hardware.

Signed-off-by: Duarte Nunes <duarte.m.nunes@gmail.com>
Merge pull request #15534 from ktoso/port-simple-fsm-redelivery-sample-ktoso

=sam #12702 Create FsmSimpleRedelivery sample (for validation).
Merge pull request #15546 from ktoso/port-removeGuardOnLoglevelRead-ktoso

=act #15488 Removed guard around _logLevel (for validation)
=doc #15543 link to persistence in java docs should point to java persistence