=act #3738 Fix memory leaks in tests

* afterAll not called when all tests marked as ignore,
  invokeBeforeAllAndAfterAllEvenIfNoTestsAreExpected = true
  should solve that, but changed to pending in Ticket1978 anyway
* Try to shutdown when ActorSystem init fails. It is difficult
  to cover all scenarios, but this should improve the situation.
  This was the reason why DeployerSpec leaked.
* missing shutdown in some tests
Merge pull request #1936 from akka/wip-3738-memory-leaks-in-tests-patriknw

=act #3738 Fix memory leaks in tests