Revert "Add session keep alive. If client doesn't send a keep alive, after a"

This reverts commit 1b0d363ffe.

handlers/ws.go

@@ -6,7 +6,6 @@ import (
 
 	"github.com/googollee/go-socket.io"
 	"github.com/gorilla/mux"
-	"github.com/play-with-docker/play-with-docker/event"
 )
 
 func WS(so socketio.Socket) {
@@ -66,10 +65,6 @@ func WS(so socketio.Socket) {
 		m.Close()
 		core.ClientClose(client)
 	})
-
-	so.On("session keep alive", func() {
-		e.Emit(event.SESSION_KEEP_ALIVE, sessionId)
-	})
 }
 
 func WSError(so socketio.Socket) {