LPS-37434 Remote staging in background

Hey Julio,

I've squashed some commits, but nothing big change.

The only thing I've modified the exception handling - the remote exceptions. 3 of them are being thrown in before we kick off the background task. Before we do anything we check the connection status for example. I did not move that to the background task executor since they user should know if the connection has a problem before the background task. If that's ok then kick off the background task.
I did remove the NO_LAYOUTS exception handling from the jsps though because it will be thrown from the background task so it does not make sense to keep it there.

Besides that everything is the same.

Thanks,

Máté