Make current-layout variable frame specific

[etu]

I need to research if it's possible to have variables that are globals to one frame to make the mode work better when you have more than one emacsclient connected and start switching around in both clients.

[etu]

If you with current master have two frames to the same emacs and switch layout in one of them, it might happen that the switch happens in the other frame. But it's not worse than before since it did mess up the variables and saved layouts instead.