Sorted out extra load

turns out we were never exiting the loop even when all bots left. Games now
shut down when there ever has been bots and they all leave (or are killed,
I think).

player.go

@@ -29,6 +29,7 @@ func (p *player) sender() {
 		}
 	}
 	p.ws.Close()
+	log.Printf("player %s: sender close", p.Robot.Id)
 }
 
 func (p *player) recv() {
@@ -51,6 +52,7 @@ func (p *player) recv() {
 			log.Printf("%+v", p.Robot.Stats)
 		}
 	}
+	log.Printf("player %s: recv close", p.Robot.Id)
 	p.ws.Close()
 }