+cam #3885 Add the ability to use an external camel context
=doc Fixed typos in actor documentation
+per #3906 add Java8 support for Persistence

- Provided new interfaces for akka-persistence to be usable directly
  through ReceiveBuilder/PartialFunction. Added a sample java project to
  showcase the usage of these API's with akka-persistence.
- Fixed a minor comment block in javadoc code snippet.
- Renamed java event persistor and fixed a documentation typo.
- Put back java event persistence methods in
  UntypedEventsourcedProcessor and copied them into
  AbstractEventsourcedProcessor for the sake of clarity in javadocs.
  Also corrected some doc punctuations.
- Documentation for akka-persistence java 8 lambda expressions support.
- Moved code examples referred from within lambda-persistence.rst to
  java8 compatible sample project.
- Removed remaining unwanted java8 compatible source files.
+per #3906 use AbstractActor for Java8 Persistence

- also rename and link doc chapter
=doc #3899 duration2TestDuration migration
=act #3888 add Timeout JavaDoc
=doc #3905 describe symmetric remoting requirement
!act,sam #3889 Adding Activator template FSM/become for Java with Lambda support

* Dining Hakkers Activator template for FSM and become
* Cleaup of FSM event matchers to be more usable and consistent
+pro #3906 Building persistence Java with lambda support doc code automatically
WIP, blows up
WIP blows up
rewrite for 1 CAS op instead of separate atomic int + concHashMap,
because before we could have races between setting values in the map,
and bumping the "seq number". Now those two values are in the same
object, and are CAS updated - so no race can happen between those.

The unsubscriber can still get messages out of order, because between
the CAS in the event bus and getting to the line where we send the
message to the actor (register/unregister) a thread could have parked
and another one could succees it's CAS and proceed with sending the
message. The unsubscriber will stash out-of-order messages, and unstash
them once the in-order message arrives.

Did not performance test the impact of switching to this from concurrent
hash map. Do we have some specific way of doing this // cc @patriknw?