Upgrade Akka 2.3.4, close #1600
Upgrade Akka 2.3.4, close #1600

wiacekm/gatling,pwielgolaski/gatling,wiacekm/gatling,pwielgolaski/gatling,gatling/gatling,MykolaB/gatling,timve/gatling,thkluge/gatling,timve/gatling,gatling/gatling,timve/gatling,ryez/gatling,ryez/gatling,thkluge/gatling,wiacekm/gatling,GabrielPlassard/gatling,gatling/gatling,GabrielPlassard/gatling,ryez/gatling,ryez/gatling,pwielgolaski/gatling,GabrielPlassard/gatling,wiacekm/gatling,MykolaB/gatling,gatling/gatling,thkluge/gatling,pwielgolaski/gatling,MykolaB/gatling,MykolaB/gatling,gatling/gatling,timve/gatling,GabrielPlassard/gatling,wiacekm/gatling,thkluge/gatling