Fix Gatling timeout on waiting akka to shutdown

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2018-07-03 03:44:35                                           5s elapsed
---- Requests ------------------------------------------------------------------
> Global                                                   (OK=205    KO=0     )
> Check if group exists                                    (OK=1      KO=0     )
> Create group                                             (OK=1      KO=0     )
> Check if document exists                                 (OK=1      KO=0     )
> Create Workspace as admin                                (OK=1      KO=0     )
> Grant write permission                                   (OK=1      KO=0     )
> Check if user exists                                     (OK=100    KO=0     )
> Create user                                              (OK=100    KO=0     )

---- Setup ---------------------------------------------------------------------
[##########################################################################]100%
          waiting: 0      / active: 0      / done:1     
================================================================================

Simulation org.nuxeo.sample.gatling.Sim00Setup completed in 4 seconds
java.lang.reflect.InvocationTargetException
	at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
	at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
	at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
	at java.lang.reflect.Method.invoke(Method.java:498)
	at io.gatling.mojo.MainWithArgsInFile.runMain(MainWithArgsInFile.java:50)
	at io.gatling.mojo.MainWithArgsInFile.main(MainWithArgsInFile.java:33)
Caused by: java.util.concurrent.TimeoutException: Futures timed out after [2 seconds]
	at scala.concurrent.impl.Promise$DefaultPromise.ready(Promise.scala:255)
	at scala.concurrent.impl.Promise$DefaultPromise.result(Promise.scala:259)
	at scala.concurrent.Await$.$anonfun$result$1(package.scala:215)
	at scala.concurrent.BlockContext$DefaultBlockContext$.blockOn(BlockContext.scala:53)
	at scala.concurrent.Await$.result(package.scala:142)
	at io.gatling.app.Gatling$.start(Gatling.scala:66)
	at io.gatling.app.Gatling$.fromArgs(Gatling.scala:45)
	at io.gatling.app.Gatling$.main(Gatling.scala:37)
	at io.gatling.app.Gatling.main(Gatling.scala)
	... 6 more