title: Playframework fails when there is no slash in the url
body: <p>We have a proxy which serves the following request to our play microservice:
  http:// service_host?param1=paramValue</p>
  
  <p>For this request, the parameters map is empty in the RequestHeader.</p>
  
  <p>This is due to the NettyModelConversion always expecting a '/' at the end of the host. <a href="https://github.com/playframework/playframework/blob/master/framework/src/play-netty-server/src/main/scala/play/core/server/netty/NettyModelConversion.scala#L40" rel="nofollow noreferrer">https://github.com/playframework/playframework/blob/master/framework/src/play-netty-server/src/main/scala/play/core/server/netty/NettyModelConversion.scala#L40</a></p>
  
  <p>It works fine for <a href="http://service_host/?param1=paramValue" rel="nofollow noreferrer">http://service_host/?param1=paramValue</a></p>
  
  <p>Can this be fixed?</p>