Refactored ClientActor with a new connection flow + refactored tests using Akka's TestProbe
Add a configuration entry for ask timeout in SprayConnectionPool + catch AskTimeoutException
Few renamings and comments
Merge pull request #22 from wajam/clement-fix-clientactor-race

Refactored ClientActor with a new connection flow
Merge branch 'master' into clement-fix-timeouts

Conflicts:
	src/main/scala/com/wajam/nlb/client/ClientActor.scala
	src/main/scala/com/wajam/nlb/client/SprayConnectionPool.scala
	src/main/scala/com/wajam/nlb/forwarder/ForwarderActor.scala
	src/test/scala/com/wajam/nlb/client/TestClientActor.scala
	src/test/scala/com/wajam/nlb/client/TestSprayConnectionPool.scala
Changes after review